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C++ || Char Array – Palindrome Number Checker Using A Character Array, Strlen, Strcpy, & Strcmp

July 10, 2012 admin No comments

The following is a palindromic number checking program, which demonstrates more use of character array’s, Strlen, & Strcmp.

Want sample code for a palindrome checker which works for numbers and words? Click here.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays How to reverse a character array Palindrome - What is it? Strlen Strcpy Strcmp Isdigit Atoi - Convert a char array to a number Do/While Loops For Loops

This program first asks the user to enter a number that they wish to compare for similarity. If the number which was entered into the system is a palindrome, the program will prompt a message to the user via cout. This program determines similarity by using the strcmp function to compare two arrays together. Using a for loop, this program also demonstrates how to reverse a character array, aswell as demonstrates how to determine if the text contained in a character array is a number or not.

This program will repeatedly prompt the user for input until an “exit code” is obtained. The designated exit code in this program is the number 0 (zero). So the program will not stop asking for user input until the number 0 is entered into the program.





		
		
			Palindrome Number Checker Using A Char Array
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jul 10, 2012
//    Taken From: http://programmingnotes.org/
//    File:  palindrome.cpp
//    Description: Palindrome number checker
// ============================================================================
#include <iostream>
#include <cctype>
#include <cstring>
#include <cstdlib>
using namespace std;

// function prototypes
void Reverse(char arry[]);
bool IsArryANum(char arry[]);

// constant, which is the exit value 
const char* EXIT_VALUE = "0";

int main()
{
    // declare variables
    char arry[80];
    char arryReversed[80];
    
    do{// get data from user using do/while loop
        cout<<"\nEnter a positive integer, or ("<<EXIT_VALUE<<") to exit: ";
        
        cin >> arry;
        
        if(atoi(arry) < 0) // check for negative numbers
        {
            cout <<"\n*** Error: "<<arry<<" must be greater than zero\n";
        }
        else if(!IsArryANum(arry)) // check for any letters 
        {
            cout <<"\n*** Error: "<<arry<<" is not an integer\n";
        }
        else if(strcmp(EXIT_VALUE, arry) == 0) // check for "exit code"
        {
            cout <<"\nExiting program...\n";
        }
        else // if all else is good, determine if number is a palindrome 
        {
            // copy the user input from the first array (arry)
            // into the second array (arryReversed)
            strcpy(arryReversed, arry);

            // function call to reverse the contents inside the
            // "arryReversed" array to check for similarity
            Reverse(arryReversed);
            
            cout <<endl<<arry;

            // use strcmp to determine if the two arrays are the same
            if(strcmp(arryReversed, arry) == 0)
            {
                cout <<" is a Palindrome..\n";
            }
            else
            {
                cout <<" is NOT a Palindrome!\n";
            }
        }
    }while(strcmp(EXIT_VALUE, arry) != 0); // keep going until user enters the exit value

    cout <<"\nBYE!\n";
    
    return 0;
}// end of main

void Reverse(char arry[])
{
    // get the length of the current word in the array index
    int length = strlen(arry)-1;
    
    // increment thru each letter within the current char array index
    // reversing the order of the array
    for (int currentChar=0; currentChar < length; --length, ++currentChar)
    {
        // copy 1st letter in the array index into temp
        char temp = arry[currentChar];
        // copy last letter in the array index into the 1st array index
        arry[currentChar] = arry[length];
        // copy temp into last array index
        arry[length] = temp;
    }
}// end of Reverse

bool IsArryANum(char arry[])
{
    // LOOP UNTIL U REACH THE NULL CHARACTER,
    // AKA THE END OF THE CHAR ARRAY
    for(int x=0; arry[x]!='\0'; ++x)
    {               
        // if the current char isnt a number,
        // exit the loop & return false
        if(!isdigit(arry[x])) 
        {
            return false;
        }
    }
    return true;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Jul 10, 2012
//    Taken From: http://programmingnotes.org/
//    File:  palindrome.cpp
//    Description: Palindrome number checker
// ============================================================================
#include <iostream>
#include <cctype>
#include <cstring>
#include <cstdlib>
using namespace std;
 
// function prototypes
void Reverse(char arry[]);
bool IsArryANum(char arry[]);
 
// constant, which is the exit value 
const char* EXIT_VALUE = "0";
 
int main()
{
    // declare variables
    char arry[80];
    char arryReversed[80];
    
    do{// get data from user using do/while loop
        cout<<"\nEnter a positive integer, or ("<<EXIT_VALUE<<") to exit: ";
        
        cin >> arry;
        
        if(atoi(arry) < 0) // check for negative numbers
        {
            cout <<"\n*** Error: "<<arry<<" must be greater than zero\n";
        }
        else if(!IsArryANum(arry)) // check for any letters 
        {
            cout <<"\n*** Error: "<<arry<<" is not an integer\n";
        }
        else if(strcmp(EXIT_VALUE, arry) == 0) // check for "exit code"
        {
            cout <<"\nExiting program...\n";
        }
        else // if all else is good, determine if number is a palindrome 
        {
            // copy the user input from the first array (arry)
            // into the second array (arryReversed)
            strcpy(arryReversed, arry);
 
            // function call to reverse the contents inside the
            // "arryReversed" array to check for similarity
            Reverse(arryReversed);
            
            cout <<endl<<arry;
 
            // use strcmp to determine if the two arrays are the same
            if(strcmp(arryReversed, arry) == 0)
            {
                cout <<" is a Palindrome..\n";
            }
            else
            {
                cout <<" is NOT a Palindrome!\n";
            }
        }
    }while(strcmp(EXIT_VALUE, arry) != 0); // keep going until user enters the exit value
 
    cout <<"\nBYE!\n";
    
    return 0;
}// end of main
 
void Reverse(char arry[])
{
    // get the length of the current word in the array index
    int length = strlen(arry)-1;
    
    // increment thru each letter within the current char array index
    // reversing the order of the array
    for (int currentChar=0; currentChar < length; --length, ++currentChar)
    {
        // copy 1st letter in the array index into temp
        char temp = arry[currentChar];
        // copy last letter in the array index into the 1st array index
        arry[currentChar] = arry[length];
        // copy temp into last array index
        arry[length] = temp;
    }
}// end of Reverse
 
bool IsArryANum(char arry[])
{
    // LOOP UNTIL U REACH THE NULL CHARACTER,
    // AKA THE END OF THE CHAR ARRAY
    for(int x=0; arry[x]!='\0'; ++x)
    {               
        // if the current char isnt a number,
        // exit the loop & return false
        if(!isdigit(arry[x])) 
        {
            return false;
        }
    }
    return true;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

Enter a positive integer, or (0) to exit: L33T
*** error: "L33T" is not an integer Enter a positive integer, or (0) to exit: -728 *** error: -728 must be greater than zero Enter a positive integer, or (0) to exit: 1858 1858 is NOT a Palindrome! Enter a positive integer, or (0) to exit: 7337 7337 is a Palindrome.. Enter a positive integer, or (0) to exit: 0 Exiting program...
BYE!

C++ || Convert Time From Seconds Into Hours, Min, Sec Format

May 30, 2012 admin 5 Comments

Here is another simple programming assignment. This page will demonstrate how to convert time from -seconds- into HH::MM::SS (hours, minutes seconds) format. So for example, if you had an input time of 9630 seconds, the program would display the converted time of 2 hours, 40 minutes, and 30 seconds.

Using simple math, this program utilizes the modulus operator, and the division operator during the conversion process.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Modulus - What is it? How Many Seconds Are In One Hour? How Many Seconds Are In One Minute?





		
		
			Convert Seconds Into HH::MM::SS Format
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 30, 2012
//    Taken From: http://programmingnotes.org/
//    File:  Convert-Time.cpp
//    Description: Demonstrates how to convert time from -seconds- into
//      HH::MM::SS (hours, minutes, seconds) format
// ============================================================================
#include <iostream>
using namespace std;

int main()
{
    // declare variables
    int time = 0;
    int hour = 0;
    int min = 0;
    int sec = 0;

    // obtain data from user
    cout << "Enter a time in seconds: ";
    cin >> time;

    // using the time from ^ above, convert
    // secs to HH:MM:SS format using division
    // and modulus
    hour = time/3600;
    time = time%3600;
    min = time/60;
    time = time%60;
    sec = time;

    // display data to user
    cout<<"\nThe time in HH:MM:SS format is: "<<hour<<" hours, "
        <<min<<" minutes, and "<<sec<<" seconds!\n";

    return 0;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 30, 2012
//    Taken From: http://programmingnotes.org/
//    File:  Convert-Time.cpp
//    Description: Demonstrates how to convert time from -seconds- into
//      HH::MM::SS (hours, minutes, seconds) format
// ============================================================================
#include <iostream>
using namespace std;
 
int main()
{
    // declare variables
    int time = 0;
    int hour = 0;
    int min = 0;
    int sec = 0;
 
    // obtain data from user
    cout << "Enter a time in seconds: ";
    cin >> time;
 
    // using the time from ^ above, convert
    // secs to HH:MM:SS format using division
    // and modulus
    hour = time/3600;
    time = time%3600;
    min = time/60;
    time = time%60;
    sec = time;
 
    // display data to user
    cout<<"\nThe time in HH:MM:SS format is: "<<hour<<" hours, "
        <<min<<" minutes, and "<<sec<<" seconds!\n";
 
    return 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: the code was compiled five separate times to display different output)

====== RUN 1 ======
Enter a time in seconds: 9630 The time in HH:MM:SS format is: 2 hours, 40 minutes, and 30 seconds! ====== RUN 2 ====== Enter a time in seconds: 7200 The time in HH:MM:SS format is: 2 hours, 0 minutes, and 0 seconds! ====== RUN 3 ====== Enter a time in seconds: 45 The time in HH:MM:SS format is: 0 hours, 0 minutes, and 45 seconds! ====== RUN 4 ====== Enter a time in seconds: 134 The time in HH:MM:SS format is: 0 hours, 2 minutes, and 14 seconds! ====== RUN 5 ====== Enter a time in seconds: 31536000
The time in HH:MM:SS format is: 8760 hours, 0 minutes, and 0 seconds!

C++ || Char Array – Determine If A String Is A Number Or Not

May 24, 2012 admin No comments

The following is another intermediate homework assignment which was presented in a C++ programming course. This program was assigned to introduce more practice using and manipulating character arrays.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Character Arrays Cin.getline Strlen - Get The Length Of A Char Array Isalpha Isspace

This program first prompts the user to input a line of text. After it obtains data from the user, using a for loop, it then displays the the string to the screen one letter (char) at a time. If the current character at that specific array index is a letter, a “flag” is set, indicating that the current word which is being displayed is not a number. If the “flag” is not set, the current word is indeed a number.

This program has the ability to intake multiple words at a time, so for example, if the user input was “Hello World 2012” the program would display the output:

Hello is NOT a number! World is NOT a number! 2012 is a number..





		
		
			Determine If A String Is A Number Or Not
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 24, 2012
//    Taken From: http://programmingnotes.org/
//    File:  isNumber.cpp
//    Description: Demonstrates checking if a char array is a number
// ============================================================================
#include <iostream>
#include <cstring>
#include <cctype>
using namespace std;

// function prototype
void IsArryANum(char arry[]);

int main()
{
    // declare & initialize variables
    char arry[256];

    // obtain data from user
    cout << "Enter some text to see if its a number or not: "; 
    cin.getline(arry, sizeof(arry)); // getting line
    
    cout<<endl;         
    IsArryANum(arry);

    return 0;
}// end of main

void IsArryANum(char arry[])
{
    int notANumber = 0;
    int length = strlen(arry);
    
    // get the length of the char array
    // and place a [space] at the end of it. Then
    // set the array index after the [space] to NULL    
    arry[length] = ' ';
    arry[length + 1] = '\0';
    
    // increment the length to account for the space we just added
    ++length;
    
    for(int x = 0; x < length; ++x)
    {       
        cout <<arry[x]; // display the char at the current index

        // if the current char isnt a number, increment counter
        if(isalpha(arry[x])) 
        {
            ++notANumber;
        }
        // if curerent char is a space, that indicates we are 
        // at the end of the current word, so we 
        // display the results to the user
        else if(isspace(arry[x])) 
        {
            if (notANumber > 0)
            {               
                cout <<"is NOT a number!"
                    <<" There are "<<notANumber<<" letters"
                    <<" in that word...\n";
            }           
            else
            {
                cout <<"is a number..\n";
            }
            notANumber = 0;
        }
    }
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   May 24, 2012
//    Taken From: http://programmingnotes.org/
//    File:  isNumber.cpp
//    Description: Demonstrates checking if a char array is a number
// ============================================================================
#include <iostream>
#include <cstring>
#include <cctype>
using namespace std;
 
// function prototype
void IsArryANum(char arry[]);
 
int main()
{
    // declare & initialize variables
    char arry[256];
 
    // obtain data from user
    cout << "Enter some text to see if its a number or not: "; 
    cin.getline(arry, sizeof(arry)); // getting line
    
    cout<<endl;         
    IsArryANum(arry);
 
    return 0;
}// end of main
 
void IsArryANum(char arry[])
{
    int notANumber = 0;
    int length = strlen(arry);
    
    // get the length of the char array
    // and place a [space] at the end of it. Then
    // set the array index after the [space] to NULL    
    arry[length] = ' ';
    arry[length + 1] = '\0';
    
    // increment the length to account for the space we just added
    ++length;
    
    for(int x = 0; x < length; ++x)
    {       
        cout <<arry[x]; // display the char at the current index
 
        // if the current char isnt a number, increment counter
        if(isalpha(arry[x])) 
        {
            ++notANumber;
        }
        // if curerent char is a space, that indicates we are 
        // at the end of the current word, so we 
        // display the results to the user
        else if(isspace(arry[x])) 
        {
            if (notANumber > 0)
            {               
                cout <<"is NOT a number!"
                    <<" There are "<<notANumber<<" letters"
                    <<" in that word...\n";
            }           
            else
            {
                cout <<"is a number..\n";
            }
            notANumber = 0;
        }
    }
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: the code was compiled three separate times to display different output)

====== RUN 1 ======
Enter some text to see if its a number or not: My Programming Notes My is NOT a number! There are 2 letters in that word... Programming is NOT a number! There are 11 letters in that word... Notes is NOT a number! There are 5 letters in that word... ====== RUN 2 ====== Enter some text to see if its a number or not: May 30th 2012 May is NOT a number! There are 3 letters in that word... 30th is NOT a number! There are 2 letters in that word... 2012 is a number.. ====== RUN 3 ====== Enter some text to see if its a number or not: 5 31 2012
5 is a number.. 31 is a number.. 2012 is a number..

C++ || Snippet – Doubly Linked List Custom Template Queue Sample Code

May 20, 2012 admin No comments

This page will consist of sample code for a custom doubly linked list template queue. This implementation is considered a doubly linked list because it uses two nodes to store data in the queue – a ‘front’ and a ‘rear’ node. This is not a circular linked list, nor does it link forwards and/or backwards.

Looking for sample code for a stack? Click here.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Structs Classes Template Classes - What Are They? Queue - What is it? FIFO - First In First Out #include < queue> Linked Lists - How To Use

This template class is a custom duplication of the Standard Template Library (STL) queue class. Whether you like building your own data structures, you simply do not like to use any inbuilt functions, opting to build everything yourself, or your homework requires you make your own data structure, this sample code is really useful. I feel its beneficial building functions such as this, that way you better understand the behind the scene processes.





		
		
			#include 'DoubleQueue.h'
			
C++
			
			// ============================================================================
//    Author: K Perkins
//    Date:   May 20, 2012
//    Taken From: http://programmingnotes.org/
//    File:  DoubleQueue.h
//    Description: This is a class which implements various functions
//          demonstrating the use of a queue. 
// ============================================================================
#include <iostream>

template <class ItemType>
class DoubleQueue
{
public:
	DoubleQueue();
		/*   Function: Constructor initializes queue 
			Precondition: None
			Postcondition: Defines private variables */
	bool IsEmpty();
		/*   Function: Determines whether queue is empty
			Precondition: Queue has been created
			Postcondition: The function = true if the queue is empty and the
							 function = false if queue is not empty */
	bool  IsFull();
		/*   Function: Determines whether queue is full
			Precondition: Queue has been created
			Postcondition: The function = true if the queue is full and the
							 function = false if queue is not full */
	void EnQueue(ItemType item);
		/*   Function: Adds new item to the back of the queue
			Precondition:  Queue has been created and is not full
			Postcondition: Item is in the queue */
	ItemType DeQueue();
		/*   Function: Returns and then deletes the first item in the queue
			Precondition:  Queue has been created and is not empty
			Postcondition: The first item in the queue has been removed and the queue
								order is maintained */
	ItemType Front();
		/*   Function: Returns (but does not delete) the first item in the queue
			Precondition:  Queue has been created and is not empty
			Postcondition: The first item in the queue has been returned and the queue
								order is maintained */
	ItemType Rear();
		/*   Function: Returns (but does not delete) the last item in the queue
			Precondition:  Queue has been created and is not empty
			Postcondition: The last item in the queue has been returned and the queue
								order is maintained */
	int Size();
          /*   Function: Return the current size of the queue
               Precondition: Queue has been initialized
               Postcondition: The size of the queue is returned */ 
	void MakeEmpty();
		/*   Function: Initializes queue to an empty state 
			Precondition: Queue has been created
			Postcondition: Queue no longer exists */
	~DoubleQueue();
		/*   Function: Removes the queue 
			Precondition: Queue has been declared
			Postcondition: Queue no longer exists */
private:
	struct  NodeType
	{
		ItemType currentItem;
		NodeType* next;
	};
	NodeType* front;	// front of queue 
	NodeType* rear;		// back of queue
	int size;
};

//=========================  Implementation  ================================//

template<class ItemType>
DoubleQueue<ItemType>::DoubleQueue()
{
	front = NULL;
	rear = NULL;
	size = 0;
}/* end of DoubleQueue */

template<class ItemType>
bool DoubleQueue<ItemType>::IsEmpty()
{
	return (front == NULL);
}/* end of IsEmpty */

template<class ItemType>
bool DoubleQueue<ItemType>::IsFull()
{	
	try
	{
		NodeType* location = new NodeType;
		delete location;
		return false;
	}
	catch(std::bad_alloc&)
	{
		return true;
	}
}/* end of IsFull */

template<class ItemType>
void DoubleQueue<ItemType>::EnQueue(ItemType newItem)
{
	if(IsFull())
	{
		std::cout<<"nQUEUE FULLn";
	}
	else
	{
		NodeType* newNode = new NodeType; // adds new node
		newNode-> currentItem = newItem;
		newNode-> next = NULL;
	
		if(rear == NULL)
		{
			front = newNode;
		}
		else
		{
			rear-> next = newNode;			
		}
		rear = newNode;
		++size;
	}
}/* end of EnQueue */

template<class ItemType>
ItemType DoubleQueue<ItemType>::DeQueue() 
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	else
	{
		NodeType* tempPtr = front; // temporary pointer
		
		ItemType item = front-> currentItem;
		front = front-> next;

		if(front == NULL)
		{
			rear = NULL;
		}
		delete tempPtr;
		--size;
		return item;
	}	
}/* end of DeQueue */

template<class ItemType>
ItemType DoubleQueue<ItemType>::Front() 
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	else
	{
		return front-> currentItem;
	}	
}/* end of Front */

template<class ItemType>
ItemType DoubleQueue<ItemType>::Rear() 
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	else
	{		
		return rear-> currentItem;
	}	
}/* end of Rear */

template<class ItemType>
int DoubleQueue<ItemType>::Size()
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	return size;
}/* end of Size */

template<class ItemType>
void DoubleQueue<ItemType>::MakeEmpty()
{
	if(!IsEmpty())
	{
		std::cout << "Destroying nodes ...n";
		while(!IsEmpty())
		{
			NodeType* tempPtr = front;
			//std::cout << tempPtr-> currentItem << 'n';
			front = front-> next;
			delete tempPtr;
		}
		rear = NULL;
		size = 0;
	}
}/* end of MakeEmpty */

template<class ItemType>
DoubleQueue<ItemType>::~DoubleQueue() 
{
	MakeEmpty();
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: K Perkins
//    Date:   May 20, 2012
//    Taken From: http://programmingnotes.org/
//    File:  DoubleQueue.h
//    Description: This is a class which implements various functions
//          demonstrating the use of a queue. 
// ============================================================================
#include <iostream>
 
template <class ItemType>
class DoubleQueue
{
public:
	DoubleQueue();
		/*   Function: Constructor initializes queue 
			Precondition: None
			Postcondition: Defines private variables */
	bool IsEmpty();
		/*   Function: Determines whether queue is empty
			Precondition: Queue has been created
			Postcondition: The function = true if the queue is empty and the
							 function = false if queue is not empty */
	bool  IsFull();
		/*   Function: Determines whether queue is full
			Precondition: Queue has been created
			Postcondition: The function = true if the queue is full and the
							 function = false if queue is not full */
	void EnQueue(ItemType item);
		/*   Function: Adds new item to the back of the queue
			Precondition:  Queue has been created and is not full
			Postcondition: Item is in the queue */
	ItemType DeQueue();
		/*   Function: Returns and then deletes the first item in the queue
			Precondition:  Queue has been created and is not empty
			Postcondition: The first item in the queue has been removed and the queue
								order is maintained */
	ItemType Front();
		/*   Function: Returns (but does not delete) the first item in the queue
			Precondition:  Queue has been created and is not empty
			Postcondition: The first item in the queue has been returned and the queue
								order is maintained */
	ItemType Rear();
		/*   Function: Returns (but does not delete) the last item in the queue
			Precondition:  Queue has been created and is not empty
			Postcondition: The last item in the queue has been returned and the queue
								order is maintained */
	int Size();
          /*   Function: Return the current size of the queue
               Precondition: Queue has been initialized
               Postcondition: The size of the queue is returned */ 
	void MakeEmpty();
		/*   Function: Initializes queue to an empty state 
			Precondition: Queue has been created
			Postcondition: Queue no longer exists */
	~DoubleQueue();
		/*   Function: Removes the queue 
			Precondition: Queue has been declared
			Postcondition: Queue no longer exists */
private:
	struct  NodeType
	{
		ItemType currentItem;
		NodeType* next;
	};
	NodeType* front;	// front of queue 
	NodeType* rear;		// back of queue
	int size;
};
 
//=========================  Implementation  ================================//
 
template<class ItemType>
DoubleQueue<ItemType>::DoubleQueue()
{
	front = NULL;
	rear = NULL;
	size = 0;
}/* end of DoubleQueue */
 
template<class ItemType>
bool DoubleQueue<ItemType>::IsEmpty()
{
	return (front == NULL);
}/* end of IsEmpty */
 
template<class ItemType>
bool DoubleQueue<ItemType>::IsFull()
{	
	try
	{
		NodeType* location = new NodeType;
		delete location;
		return false;
	}
	catch(std::bad_alloc&)
	{
		return true;
	}
}/* end of IsFull */
 
template<class ItemType>
void DoubleQueue<ItemType>::EnQueue(ItemType newItem)
{
	if(IsFull())
	{
		std::cout<<"nQUEUE FULLn";
	}
	else
	{
		NodeType* newNode = new NodeType; // adds new node
		newNode-> currentItem = newItem;
		newNode-> next = NULL;
	
		if(rear == NULL)
		{
			front = newNode;
		}
		else
		{
			rear-> next = newNode;			
		}
		rear = newNode;
		++size;
	}
}/* end of EnQueue */
 
template<class ItemType>
ItemType DoubleQueue<ItemType>::DeQueue() 
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	else
	{
		NodeType* tempPtr = front; // temporary pointer
		
		ItemType item = front-> currentItem;
		front = front-> next;
 
		if(front == NULL)
		{
			rear = NULL;
		}
		delete tempPtr;
		--size;
		return item;
	}	
}/* end of DeQueue */
 
template<class ItemType>
ItemType DoubleQueue<ItemType>::Front() 
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	else
	{
		return front-> currentItem;
	}	
}/* end of Front */
 
template<class ItemType>
ItemType DoubleQueue<ItemType>::Rear() 
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	else
	{		
		return rear-> currentItem;
	}	
}/* end of Rear */
 
template<class ItemType>
int DoubleQueue<ItemType>::Size()
{
	if(IsEmpty())
	{
		std::cout<<"nQUEUE EMPTYn";
	}
	return size;
}/* end of Size */
 
template<class ItemType>
void DoubleQueue<ItemType>::MakeEmpty()
{
	if(!IsEmpty())
	{
		std::cout << "Destroying nodes ...n";
		while(!IsEmpty())
		{
			NodeType* tempPtr = front;
			//std::cout << tempPtr-> currentItem << 'n';
			front = front-> next;
			delete tempPtr;
		}
		rear = NULL;
		size = 0;
	}
}/* end of MakeEmpty */
 
template<class ItemType>
DoubleQueue<ItemType>::~DoubleQueue() 
{
	MakeEmpty();
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

===== DEMONSTRATION HOW TO USE =====

Use of the above template class is the same as its STL counterpart. Here is a sample program demonstrating its use.





		
		
			How To Use #include 'DoubleQueue.h'
			
C++
			
			#include <iostream>
#include "DoubleQueue.h"
using namespace std;

int main()
{
	// declare variables
	DoubleQueue<char> charQueue;
	DoubleQueue<int> intQueue;
	DoubleQueue<float> floatQueue;
	
	// ------ Char Example ------//
	char charArry[]="My Programming Notes Helped Me Succeed!";
	int counter=0;	
	while(charArry[counter]!='\0')
	{
		charQueue.EnQueue(charArry[counter]);
		++counter;
	}
	cout<<"charQueue has "<<charQueue.Size()<<" items in it "
		<<"and contains the text:n";
	while(!charQueue.IsEmpty())
	{
		cout<<charQueue.DeQueue();
	}
	cout<<endl;
	
	// ------ Int Example ------//
	int intArry[]={1,22,3,46,5,66,7,8,1987};
	counter=0;
	while(counter<9)
	{
		intQueue.EnQueue(intArry[counter]);
		++counter;
	}
	cout<<"nintQueue has "<<intQueue.Size()<<" items in it.n"
		<<"The sum of the numbers in the queue is: ";
	counter=0;
	while(!intQueue.IsEmpty())
	{
		counter-=intQueue.DeQueue();
	}
	cout<<counter<<endl;
	
	// ------ Float Example ------//
	float floatArry[]={41.6,2.8,43.9,4.4,19.87,6.23,7.787,68.99,9.6,81.540};
	float sum=0;
	counter=0;
	while(counter<10)
	{
		floatQueue.EnQueue(floatArry[counter]);
		++counter;
	}
	cout<<"nfloatQueue has "<<floatQueue.Size()<<" items in it.n"
		<<"The sum of the numbers in the queue is: ";
	while(!floatQueue.IsEmpty())
	{
		sum-=floatQueue.DeQueue();
	}
	cout<<sum<<endl;

	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
#include "DoubleQueue.h"
using namespace std;
 
int main()
{
	// declare variables
	DoubleQueue<char> charQueue;
	DoubleQueue<int> intQueue;
	DoubleQueue<float> floatQueue;
	
	// ------ Char Example ------//
	char charArry[]="My Programming Notes Helped Me Succeed!";
	int counter=0;	
	while(charArry[counter]!='\0')
	{
		charQueue.EnQueue(charArry[counter]);
		++counter;
	}
	cout<<"charQueue has "<<charQueue.Size()<<" items in it "
		<<"and contains the text:n";
	while(!charQueue.IsEmpty())
	{
		cout<<charQueue.DeQueue();
	}
	cout<<endl;
	
	// ------ Int Example ------//
	int intArry[]={1,22,3,46,5,66,7,8,1987};
	counter=0;
	while(counter<9)
	{
		intQueue.EnQueue(intArry[counter]);
		++counter;
	}
	cout<<"nintQueue has "<<intQueue.Size()<<" items in it.n"
		<<"The sum of the numbers in the queue is: ";
	counter=0;
	while(!intQueue.IsEmpty())
	{
		counter-=intQueue.DeQueue();
	}
	cout<<counter<<endl;
	
	// ------ Float Example ------//
	float floatArry[]={41.6,2.8,43.9,4.4,19.87,6.23,7.787,68.99,9.6,81.540};
	float sum=0;
	counter=0;
	while(counter<10)
	{
		floatQueue.EnQueue(floatArry[counter]);
		++counter;
	}
	cout<<"nfloatQueue has "<<floatQueue.Size()<<" items in it.n"
		<<"The sum of the numbers in the queue is: ";
	while(!floatQueue.IsEmpty())
	{
		sum-=floatQueue.DeQueue();
	}
	cout<<sum<<endl;
 
	return 0;
}// http://programmingnotes.org/

Once compiled, you should get this as your output

charQueue has 39 items in it and contains the text: My Programming Notes Helped Me Succeed!
intQueue has 9 items in it. The sum of the numbers in the queue is: -2145
floatQueue has 10 items in it. The sum of the numbers in the queue is: -286.717

C++ || Snippet – How To Find The Minimum & Maximum Of 3 Numbers, Print In Ascending Order

April 29, 2012 admin No comments

This page will demonstrate how to find the minimum and maximum of 3 numbers. After the maximum and minimum numbers are obtained, the 3 numbers are displayed to the screen in ascending order.

This program uses multiple if-statements to determine equality, and uses 3 seperate int varables to store its data. This program is very basic, so it does not utilize an integer array, or any sorting methods.

NOTE: If you want to find the Minimum & Maximum of numbers contained in an integer array, click here.





		
		
			Find The Minimum & Maximum Of 3 Numbers
			
C++
			
			// ============================================================================
//    Author: K Perkins
//    Date:   Apr 29, 2012
//    Taken From: http://programmingnotes.org/
//    File:  min_mid_max.cpp
//    Description: Demonstrates how to find the minimum & maximum of 3 numbers
// ============================================================================
#include <iostream>
using namespace std;

int main()
{
    // declare variables
    int a=0;
    int b=0;
    int c=0;
    int max=0;
    int min=0;
    int middle=0;
    
    // get data from user
    cout<<"Please enter 3 numbers: ";
    cin >> a >> b >> c;
    
    // display information back to the user
    cout <<"The numbers you just entered are: "<<a<<" "<<b<<" "<<c<<endl;
    
    // check for the highest number
    if(a > b && a > c)
    {
        max = a;
    }
    else if(b > a && b > c)
    {
        max = b;
    }
    else
    {
        max = c;
    }
    
    // check for the lowest number
    if(a < b && a < c)
    {
        min = a;
    }
    else if(b < a && b < c)
    {
        min = b;
    }
    else
    {
        min = c;
    }
    
    // use the 'min' and 'max' variables from above ^ to find
    // the 'middle' value
    if((max == a && min == b) || (max == b && min == a))
    {
        middle = c;
    }
    else if((max == b && min == c) || (max == c && min == b))
    {
        middle = a;
    }
    else
    {
        middle = b;
    }
    
    // display data to the screen
    cout<<"nThe maximum number is: "<<max;
    cout<<"nThe minimum number is: "<<min;
    cout<<"nThe numbers in order are: "<<min<<" "<<middle<< " "<<max<<endl;
    
    return 0;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: K Perkins
//    Date:   Apr 29, 2012
//    Taken From: http://programmingnotes.org/
//    File:  min_mid_max.cpp
//    Description: Demonstrates how to find the minimum & maximum of 3 numbers
// ============================================================================
#include <iostream>
using namespace std;
 
int main()
{
    // declare variables
    int a=0;
    int b=0;
    int c=0;
    int max=0;
    int min=0;
    int middle=0;
    
    // get data from user
    cout<<"Please enter 3 numbers: ";
    cin >> a >> b >> c;
    
    // display information back to the user
    cout <<"The numbers you just entered are: "<<a<<" "<<b<<" "<<c<<endl;
    
    // check for the highest number
    if(a > b && a > c)
    {
        max = a;
    }
    else if(b > a && b > c)
    {
        max = b;
    }
    else
    {
        max = c;
    }
    
    // check for the lowest number
    if(a < b && a < c)
    {
        min = a;
    }
    else if(b < a && b < c)
    {
        min = b;
    }
    else
    {
        min = c;
    }
    
    // use the 'min' and 'max' variables from above ^ to find
    // the 'middle' value
    if((max == a && min == b) || (max == b && min == a))
    {
        middle = c;
    }
    else if((max == b && min == c) || (max == c && min == b))
    {
        middle = a;
    }
    else
    {
        middle = b;
    }
    
    // display data to the screen
    cout<<"nThe maximum number is: "<<max;
    cout<<"nThe minimum number is: "<<min;
    cout<<"nThe numbers in order are: "<<min<<" "<<middle<< " "<<max<<endl;
    
    return 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

Please enter 3 numbers: 89 56 1987 The numbers you just entered are: 89 56 1987
The maximum number is: 1987 The minimum number is: 56 The numbers in order are: 56 89 1987

C++ || Snippet – How To Read & Write Data From A User Specified Text File

April 29, 2012 admin No comments

This page will consist of a demonstration of a simple quadratic formula program, which highlights the use of the input/output mechanisms of manipulating a text file. This program is very similar to an earlier snippet which was presented on this site, but in this example, the user has the option of choosing which file they want to manipulate. This program also demonstrates how to read in data from a file (numbers), manipulate that data, and output new data into a different text file.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Fstream Ifstream Ofstream Working With Files C_str() - Convert A String To Char Array Equivalent Getline - String Version

Note: The data file that is used in this example can be downloaded here.

Also, in order to read in the data .txt file, you need to save the .txt file in the same directory (or folder) as your .cpp file is saved in. If you are using Visual C++, this directory will be located in

Documents > Visual Studio 2010 > Projects > [Your project name] > [Your project name]





		
		
			User Specified Input/Output Manipulation
			
C++
			
			#include <iostream>
#include <fstream>
#include <string>
#include <cmath>
#include <cstdlib>
using namespace std;

int main() 
{
    // declare variables
    // char fileName[80];
    string fileName;    
    ifstream infile;
    ofstream outfile;
    double a=0,b=0,c=0;
    double root1=0, root2=0;    
    
    // get the name of the file from the user
    cout << "Please enter the name of the file: ";    
    getline(cin, fileName);
    
    // ^ you could also use a character array instead
    // of a string. Your getline declaration would look
    // like this:
    // ---------------------------------------------
    // cin.getline(fileName,80);


    // this opens the input file
    // NOTE: you need to convert the string to a 
    // char array using the function "c_str()"
    infile.open(fileName.c_str());
    
    // ^  if you used a char array as the file name instead 
    // of a string, the declaration to open the file 
    // would look like this:
    // ---------------------------------------------
    // infile.open(fileName);
    
    // check to see if the file even exists, & if not then EXIT
    if(infile.fail())
    {
        cout<<"nError, the input file could not be found!n";
        exit(1);
    }
    
    // this opens the output file
    // if the file doesnt already exist, it will be created
    outfile.open("OUTPUT_Quadratic_programmingnotes_freeweq_com.txt");  
    
    // this loop reads in data until there is no more 
    // data contained in the file
    while(infile.peek() != EOF)
    {
        // this assigns the incoming data to the
        // variables 'a', 'b' and 'c'
        // NOTE: it is just like a cin >> statement
        infile>> a >> b>> c;

        // NOTE: if you want to read data into an array
        // your declaration would be like this
        // ------------------------------------ 
        // infile>> a[counter] >> b[counter] >> c[counter];
        // ++counter;
    }    
    
    // this does the quadratic formula calculations
    root1 = ((-b) + sqrt(pow(b,2) - (4*a*c)))/(2*a);
    root2 = ((-b) - sqrt(pow(b,2) - (4*a*c)))/(2*a);

    // this displays the numbers to screen via cout
    cout <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    cout <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;
     
    // this saves the data to the output file
    // NOTE: its almost exactly the same as the cout statement
    outfile <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    outfile <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;

    // close the input/output files once you are done using them
    infile.close();
    outfile.close();

    // stops the program from automatically closing
    cout<<"nPress ENTER to continue...";
    cin.get();

    return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
#include <fstream>
#include <string>
#include <cmath>
#include <cstdlib>
using namespace std;
 
int main() 
{
    // declare variables
    // char fileName[80];
    string fileName;    
    ifstream infile;
    ofstream outfile;
    double a=0,b=0,c=0;
    double root1=0, root2=0;    
    
    // get the name of the file from the user
    cout << "Please enter the name of the file: ";    
    getline(cin, fileName);
    
    // ^ you could also use a character array instead
    // of a string. Your getline declaration would look
    // like this:
    // ---------------------------------------------
    // cin.getline(fileName,80);
 
 
    // this opens the input file
    // NOTE: you need to convert the string to a 
    // char array using the function "c_str()"
    infile.open(fileName.c_str());
    
    // ^  if you used a char array as the file name instead 
    // of a string, the declaration to open the file 
    // would look like this:
    // ---------------------------------------------
    // infile.open(fileName);
    
    // check to see if the file even exists, & if not then EXIT
    if(infile.fail())
    {
        cout<<"nError, the input file could not be found!n";
        exit(1);
    }
    
    // this opens the output file
    // if the file doesnt already exist, it will be created
    outfile.open("OUTPUT_Quadratic_programmingnotes_freeweq_com.txt");  
    
    // this loop reads in data until there is no more 
    // data contained in the file
    while(infile.peek() != EOF)
    {
        // this assigns the incoming data to the
        // variables 'a', 'b' and 'c'
        // NOTE: it is just like a cin >> statement
        infile>> a >> b>> c;
 
        // NOTE: if you want to read data into an array
        // your declaration would be like this
        // ------------------------------------ 
        // infile>> a[counter] >> b[counter] >> c[counter];
        // ++counter;
    }    
    
    // this does the quadratic formula calculations
    root1 = ((-b) + sqrt(pow(b,2) - (4*a*c)))/(2*a);
    root2 = ((-b) - sqrt(pow(b,2) - (4*a*c)))/(2*a);
 
    // this displays the numbers to screen via cout
    cout <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    cout <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;
     
    // this saves the data to the output file
    // NOTE: its almost exactly the same as the cout statement
    outfile <<"For the numbersna = "<<a<<"nb = "<<b<<"nc = "<<c<<endl;
    outfile <<"nroot 1 = "<<root1<<"nroot 2 = "<<root2<<endl;
 
    // close the input/output files once you are done using them
    infile.close();
    outfile.close();
 
    // stops the program from automatically closing
    cout<<"nPress ENTER to continue...";
    cin.get();
 
    return 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

Please enter the name of the file: INPUT_Quadratic_programmingnotes_freeweq_com.txt
For the numbers a = 2 b = 4 c = -16 root 1 = 2 root 2 = -4
Press ENTER to continue...

C++ || Snippet – Custom Conio.h Sample Code For Linux

April 28, 2012 admin 1 Comment

This page will consist of a brief implementation of “conio.h” for Linux.

Conio.h is a C header file used in old MS-DOS compilers to create text user interfaces. It is not part of the C standard library, ISO C, nor is it defined by POSIX. As a result, compilers that target Unix platforms do not contain this header file, and do not implement its library functions.

Included in the sample code are the following:

(1) getch() - Reads a character directly from the console without buffer, and without echo
(2) getche() - Reads a character directly from the console without buffer, but with echo. (3) kbhit() - Determines if a keyboard key was pressed.
(4) clrscr() - Clears data from the console screen.





		
		
			Conio.h For Linux
			
C++
			
			#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>

/* Reads a character directly from the console without buffer, and without echo. */
int getch()
{
    struct termios oldattr, newattr;
    int ch;
    tcgetattr( STDIN_FILENO, &oldattr );
    newattr = oldattr;
    newattr.c_lflag &= ~( ICANON | ECHO );
    tcsetattr( STDIN_FILENO, TCSANOW, &newattr );
    ch = getchar();
    tcsetattr( STDIN_FILENO, TCSANOW, &oldattr );
    return ch;
}

/* Reads a character directly from the console without buffer, but with echo */
int getche()
{
    struct termios oldattr, newattr;
    int ch;
    tcgetattr( STDIN_FILENO, &oldattr );
    newattr = oldattr;
    newattr.c_lflag &= ~( ICANON );
    tcsetattr( STDIN_FILENO, TCSANOW, &newattr );
    ch = getchar();
    tcsetattr( STDIN_FILENO, TCSANOW, &oldattr );
    return ch;
}

/* Determines if a keyboard key was pressed */
int kbhit()
{
    struct termios oldt, newt;
    int ch;
    int oldf;

    tcgetattr(STDIN_FILENO, &oldt);
    newt = oldt;
    newt.c_lflag &= ~(ICANON | ECHO);
    tcsetattr(STDIN_FILENO, TCSANOW, &newt);
    oldf = fcntl(STDIN_FILENO, F_GETFL, 0);
    fcntl(STDIN_FILENO, F_SETFL, oldf | O_NONBLOCK);

    ch = getchar();

    tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
    fcntl(STDIN_FILENO, F_SETFL, oldf);

    if(ch != EOF)
    {
        ungetc(ch, stdin);
        return 1;
    } 
    return 0;
}

/* Clears data from the console screen */
void clrscr()
{
	char str[] = " [H [2J";
	str[3] = str[0] = 27;
	write(1, str, 7);
}// http://programmingnotes.org/
			
				
					
				
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						#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
 
/* Reads a character directly from the console without buffer, and without echo. */
int getch()
{
    struct termios oldattr, newattr;
    int ch;
    tcgetattr( STDIN_FILENO, &oldattr );
    newattr = oldattr;
    newattr.c_lflag &= ~( ICANON | ECHO );
    tcsetattr( STDIN_FILENO, TCSANOW, &newattr );
    ch = getchar();
    tcsetattr( STDIN_FILENO, TCSANOW, &oldattr );
    return ch;
}
 
/* Reads a character directly from the console without buffer, but with echo */
int getche()
{
    struct termios oldattr, newattr;
    int ch;
    tcgetattr( STDIN_FILENO, &oldattr );
    newattr = oldattr;
    newattr.c_lflag &= ~( ICANON );
    tcsetattr( STDIN_FILENO, TCSANOW, &newattr );
    ch = getchar();
    tcsetattr( STDIN_FILENO, TCSANOW, &oldattr );
    return ch;
}
 
/* Determines if a keyboard key was pressed */
int kbhit()
{
    struct termios oldt, newt;
    int ch;
    int oldf;
 
    tcgetattr(STDIN_FILENO, &oldt);
    newt = oldt;
    newt.c_lflag &= ~(ICANON | ECHO);
    tcsetattr(STDIN_FILENO, TCSANOW, &newt);
    oldf = fcntl(STDIN_FILENO, F_GETFL, 0);
    fcntl(STDIN_FILENO, F_SETFL, oldf | O_NONBLOCK);
 
    ch = getchar();
 
    tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
    fcntl(STDIN_FILENO, F_SETFL, oldf);
 
    if(ch != EOF)
    {
        ungetc(ch, stdin);
        return 1;
    } 
    return 0;
}
 
/* Clears data from the console screen */
void clrscr()
{
	char str[] = " [H [2J";
	str[3] = str[0] = 27;
	write(1, str, 7);
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Note: Not all functions in conio.h are included in the above sample code.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

===== DEMONSTRATION HOW TO USE =====

Use of the above header file is the same as its DOS counterpart, and can be utilized by simply naming the above snippet as “conio.h.” Here is a sample program demonstrating its use.





		
		
			How To Use #include 'conio.h'
			
C++
			
			#include <iostream>
#include "conio.h"
using namespace std;

int main()
{
    char userInput;

    while(!kbhit())
    {
        cout<<"Press a key!n";
    }

    userInput=getche();
    cout<<"nYou pressed '"<<userInput<<"'!n";

    cout<<"nThe screen will now clearn";
    cout<<"Press any key to continue..n";
    getch();
    clrscr();

    cout<<"The screen successfully clearedn";  	
    cout<<"Press any key to continue..n";	
    getch();

    return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
#include "conio.h"
using namespace std;
 
int main()
{
    char userInput;
 
    while(!kbhit())
    {
        cout<<"Press a key!n";
    }
 
    userInput=getche();
    cout<<"nYou pressed '"<<userInput<<"'!n";
 
    cout<<"nThe screen will now clearn";
    cout<<"Press any key to continue..n";
    getch();
    clrscr();
 
    cout<<"The screen successfully clearedn";  	
    cout<<"Press any key to continue..n";	
    getch();
 
    return 0;
}// http://programmingnotes.org/

Once compiled, you should get this as your output

Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! Press a key! p You pressed 'p'!
The screen will now clear Press any key to continue.. [ THE SCREEN CLEARS HERE ]
The screen successfully cleared Press any key to continue..

C++ || Class & Input/Output – Display The Contents Of A User Specified Text File To The Screen

April 24, 2012 admin No comments

The following is another intermediate homework assignment which was presented in a C++ programming course. This program was assigned to introduce more practice using the class data structure, which is very similar to the struct data structure.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Header Files - How To Use Them Class - What Is It? How To Read Data From A File String - Getline Array - Cin.Getline Strcpy - Copy Contents Of An Array #Define

This program first prompts the user to input a file name. After it obtains a file name from the user, it then attempts to display the contents of the user specified file to the output screen. If the file could not be found, an error message appears. If the file is found, the program continues as normal. After the file contents finishes being displayed, a summary indicating the total number of lines which has been read is also shown to the screen.

This program was implemented into 3 different files (two .cpp files, and one header file .h). So the code for this program will be broken up into 3 sections, the main file (.cpp), the header file (.h), and the implementation of the functions within the header file (.cpp).

Note: The data file that is used in this example can be downloaded here.

Documents > Visual Studio 2010 > Projects > [Your project name] > [Your project name]

======== FILE #1 – Main.cpp ========





		
		
			File #1 - Main.cpp
			
C++
			
			// ============================================================================
// File: Main.cpp 
// ============================================================================
// This program tests the "CFileDisp" object.  It prompts the user for an input
// filename, then attempts to display the contents of that file to stdout.
// After the file contents have been displayed, a summary line indicating the
// total number of lines that have been displayed is written to stdout.
// ============================================================================
#include <iostream>
#include <fstream>
#include "CFileDisp.h"
using namespace std;

// ==== main ==================================================================
//
// ============================================================================

int main()
{
	CFileDisp       myFile;
	char            fname[MAX_LENGTH];
	int             numLines;
	
	// get the filename from the user
	cout << "Enter a filename: ";
	cin.getline(fname, MAX_LENGTH);
	
	// copy the user's filename into the file object
	myFile.SetFilename(fname);
	
	// have the object open the file
	myFile.OpenFile();
	
	// if all is good and well...
	if(myFile.IsValid()==true)
	{
		numLines = myFile.DisplayFileContents();
		
		// close the file
		myFile.CloseFile();
		
		// write how many lines were displayed to stdout
		cout << "nt*** Total lines displayed: " << numLines << endl;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
// File: Main.cpp 
// ============================================================================
// This program tests the "CFileDisp" object.  It prompts the user for an input
// filename, then attempts to display the contents of that file to stdout.
// After the file contents have been displayed, a summary line indicating the
// total number of lines that have been displayed is written to stdout.
// ============================================================================
#include <iostream>
#include <fstream>
#include "CFileDisp.h"
using namespace std;
 
// ==== main ==================================================================
//
// ============================================================================
 
int main()
{
	CFileDisp       myFile;
	char            fname[MAX_LENGTH];
	int             numLines;
	
	// get the filename from the user
	cout << "Enter a filename: ";
	cin.getline(fname, MAX_LENGTH);
	
	// copy the user's filename into the file object
	myFile.SetFilename(fname);
	
	// have the object open the file
	myFile.OpenFile();
	
	// if all is good and well...
	if(myFile.IsValid()==true)
	{
		numLines = myFile.DisplayFileContents();
		
		// close the file
		myFile.CloseFile();
		
		// write how many lines were displayed to stdout
		cout << "nt*** Total lines displayed: " << numLines << endl;
	}
	
	return 0;
}// http://programmingnotes.org/

======== FILE #2 – CFileDisp.h ========

Remember, you need to name the header file the same as the #include from the Main.cpp file. This file contains the function declarations, but no implementation of those functions takes place here.





		
		
			File #2 - CFileDisp.h
			
C++
			
			// ============================================================================
// File: CFileDisp.h
// ============================================================================
// This is the header file which declares the objects which are used to open 
// a text file and display its contents to stdout.
// ============================================================================
#ifndef CFILE_DISP_HEADER
#define CFILE_DISP_HEADER

#include <fstream>
using namespace std;

#define MAX_LENGTH  256

class   CFileDisp
{
public:
	// constructor
	CFileDisp();
	
	// member functions
	void SetFilename(char  newFilename[]);
	/*  Purpose: Copy the user's filename into the file object */
	void OpenFile();
	/* Purpose: Open's the file which is specified by the user */
	bool IsValid();
	/* Purpose: Checks if the file exists. 
	   Post: Returns false if file cannot be found */
	int DisplayFileContents();
	/* Purpose: Display's the file contents to stdout
	   Post: Returns the total number of lines contained in the file */
	void CloseFile();
	/* Purpose: Closes the file */
	
	// destructor
	~CFileDisp();

private:
    bool            m_bIsValid;
    char            m_filename[MAX_LENGTH];
    ifstream        m_inFile;
};
#endif   // CFILE_DISP_HEADER // http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
// File: CFileDisp.h
// ============================================================================
// This is the header file which declares the objects which are used to open 
// a text file and display its contents to stdout.
// ============================================================================
#ifndef CFILE_DISP_HEADER
#define CFILE_DISP_HEADER
 
#include <fstream>
using namespace std;
 
#define MAX_LENGTH  256
 
class   CFileDisp
{
public:
	// constructor
	CFileDisp();
	
	// member functions
	void SetFilename(char  newFilename[]);
	/*  Purpose: Copy the user's filename into the file object */
	void OpenFile();
	/* Purpose: Open's the file which is specified by the user */
	bool IsValid();
	/* Purpose: Checks if the file exists. 
	   Post: Returns false if file cannot be found */
	int DisplayFileContents();
	/* Purpose: Display's the file contents to stdout
	   Post: Returns the total number of lines contained in the file */
	void CloseFile();
	/* Purpose: Closes the file */
	
	// destructor
	~CFileDisp();
 
private:
    bool            m_bIsValid;
    char            m_filename[MAX_LENGTH];
    ifstream        m_inFile;
};
#endif   // CFILE_DISP_HEADER // http://programmingnotes.org/

======== FILE #3 – CFileDisp.cpp ========

This is the function implementation file for the CFileDisp.h class. This file can be named anything you wish as long as you #include “CFileDisp.h”





		
		
			File #3 - CFileDisp.cpp
			
C++
			
			// ============================================================================
// File: CFileDisp.cpp
// ============================================================================
// This file implements the functions which are declared in the CFileDisp
// class, which is located in CFileDisp.h
// ============================================================================
#include <iostream>
#include <cstring>
#include <string>
#include "CFileDisp.h"
using namespace std;

CFileDisp::CFileDisp()
{
	m_bIsValid = 0;
}// end of CFileDisp

void CFileDisp::SetFilename(char  newFilename[])
{
    strcpy(m_filename,newFilename);
}// end of SetFilename

void CFileDisp::OpenFile()
{
	m_inFile.open(m_filename);
}// end of OpenFile

bool CFileDisp::IsValid()
{
	if (m_inFile.fail())
	{
		cout << m_filename << " was not found...nn";
		return false;
	}
	else 
	{
		return true;
	}
}// end of IsValid

int CFileDisp::DisplayFileContents()
{
	int total=0;
	string inLine;
	
	cout << endl;
	
	while(getline(m_inFile, inLine))
	{
		cout << inLine << endl;
		++total;
	}	
	return total;
}// end of DisplayFileContents

void CFileDisp::CloseFile()
{
	m_inFile.close();
}//	end of CloseFile

// this is the destructor
CFileDisp::~CFileDisp()
{
	m_bIsValid = 0;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
// File: CFileDisp.cpp
// ============================================================================
// This file implements the functions which are declared in the CFileDisp
// class, which is located in CFileDisp.h
// ============================================================================
#include <iostream>
#include <cstring>
#include <string>
#include "CFileDisp.h"
using namespace std;
 
CFileDisp::CFileDisp()
{
	m_bIsValid = 0;
}// end of CFileDisp
 
void CFileDisp::SetFilename(char  newFilename[])
{
    strcpy(m_filename,newFilename);
}// end of SetFilename
 
void CFileDisp::OpenFile()
{
	m_inFile.open(m_filename);
}// end of OpenFile
 
bool CFileDisp::IsValid()
{
	if (m_inFile.fail())
	{
		cout << m_filename << " was not found...nn";
		return false;
	}
	else 
	{
		return true;
	}
}// end of IsValid
 
int CFileDisp::DisplayFileContents()
{
	int total=0;
	string inLine;
	
	cout << endl;
	
	while(getline(m_inFile, inLine))
	{
		cout << inLine << endl;
		++total;
	}	
	return total;
}// end of DisplayFileContents
 
void CFileDisp::CloseFile()
{
	m_inFile.close();
}//	end of CloseFile
 
// this is the destructor
CFileDisp::~CFileDisp()
{
	m_bIsValid = 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output





		
		
			Enter a filename: input_file_display_programmingnotes_freeweq_com.txt

346     130     982     90      656     117   595
415     948     126     4       558     571   87
42      360     412     721     463     47    119
441     190     985     214     509     2     571
77      81      681     651     995     93    74
310     9       995     561     92      14    288
466     664     892     8       766     34    639
151     64      98      813     67      834   369

                This is a line of text!

        *** Total lines displayed: 10
			
				
					
				
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						Enter a filename: input_file_display_programmingnotes_freeweq_com.txt
 
346     130     982     90      656     117   595
415     948     126     4       558     571   87
42      360     412     721     463     47    119
441     190     985     214     509     2     571
77      81      681     651     995     93    74
310     9       995     561     92      14    288
466     664     892     8       766     34    639
151     64      98      813     67      834   369
 
                This is a line of text!
 
        *** Total lines displayed: 10

C++ || Class – Roman Numeral To Integer & Integer To Roman Numeral Conversion

April 10, 2012 admin No comments

Click Here For Updated Version Of Program

The following is another homework assignment which was presented in a C++ Data Structures course. This program was assigned in order to practice the use of the class data structure, which is very similar to the struct data structure.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Header Files - How To Use Them Class - What Is It? Do/While Loop Passing a Value By Reference Roman Numerals - How Do You Convert To Decimal? Online Roman Numeral Converter - Check For Correct Results

This is an interactive program in which the user has the option of selecting from 7 modes of operation. Of those modes, the user has the option of entering in roman numerals for conversion, entering in decimal numbers for conversion, displaying the recently entered number, and finally converting between roman or decimal values.

A sample of the menu is as followed:
(Where the user would enter numbers 1-7 to select a choice)





		
		
			From the following menu:

1.  Enter a Decimal number
2.  Enter a Roman Numeral
3.  Convert from Decimal to Roman
4.  Convert from Roman to Decimal
5.  Print the current Decimal number
6.  Print the current Roman Numeral
7.  Quit

Please enter a selection:
			
				
					
				
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						From the following menu:
 
1.  Enter a Decimal number
2.  Enter a Roman Numeral
3.  Convert from Decimal to Roman
4.  Convert from Roman to Decimal
5.  Print the current Decimal number
6.  Print the current Roman Numeral
7.  Quit
 
Please enter a selection:

======== FILE #1 – Menu.cpp ========

NOTE: On some compilers, you may have to add #include < cstdlib> in order for the code to compile.





		
		
			File #1 - Menu.cpp
			
C++
			
			// ============================================================================
//  File: Menu.cpp
//  Purpose: Converts a number enetered in Decimal to Roman Numeral and a 
//  Roman Numeral to a Decimal Number 
// ============================================================================
#include <iostream>
#include <iomanip>
#include <string>
#include "ClassRomanType.h"
using namespace std;

// function prototypes
void DisplayMenu();
int GetCommand(int command);
void RunChoice(int command, ClassRomanType& romanObject);

int main()
{
	int command=7;	// Holds which action the user chooses to make
	ClassRomanType	romanObject;	// Gives access to the class

	do{
		DisplayMenu();
		command = GetCommand(command);
		RunChoice(command, romanObject);
		cout<<"n--------------------------------------------------------------------n";
	}while(command!=7);

	cout<<"nBye!n";

	return 0;
}// End of main

void RunChoice(int command, ClassRomanType& romanObject)
{// Function: Execute the choice selected from the menu

	// declare private variables
	int decimalNumber=0;	// Holds decimal value
	char romanNumeral[150];	//Holds value of roman numeral

	// execute the desired choice
	cout <<"ntYou selected choice #"<<command<<" which will: ";
	switch(command)
	{
	case 1:
		cout << "Get Decimal Numbernn";
		cout <<"Enter a Decimal Number: ";
		cin >> decimalNumber;
		romanObject.GetDecimalNumber(decimalNumber);
		break;
	case 2:
		cout << "Get Roman Numeralnn";
		cout <<"nEnter a Roman Numeral: ";
		cin >> romanNumeral;
		romanObject.GetRomanNumeral(romanNumeral);
		break;
	case 3:
		cout << "Convert from Decimal to Romannn";
		romanObject.ConvertDecimalToRoman();
		cout<<"Running....nComplete!n";
		break;
	case 4:
		cout << "Convert from Roman to Decimalnn";
		romanObject.ConvertRomanToDecimal();
		cout<<"Running....nComplete!n";
		break;
	case 5:
		cout << "Print the current Decimal numbernn";
		cout<<"n The current Roman to Decimal Value is: "; 
		cout << romanObject.ReturnDecimalNumber()<<endl;
		break;
	case 6:
		cout << "Print the current Roman Numeralnn";
		cout<<"n The current Decimal to Roman Value is: "; 
		cout << romanObject.ReturnRomanNumber()<<endl;
		break;
	case 7:
		cout << "Quitnn";
		break;
	default:
		cout << "nError, you entered an invalid command!nPlease try again...";
		break;
	}
}//End of RunChoice

int GetCommand(int command)
{// Function: Gets choice from menu
	cout <<"nPlease enter a selection: ";
	cin>> command;
	return command;
}// End of GetCommand

void DisplayMenu()
{// Function: Displays menu
	cout <<"From the following menu:n"<<endl;
	cout <<left<<setw(2)<<"1."<<left<<setw(15)<<"  Enter a Decimal number"<<endl;
	cout <<left<<setw(2)<<"2."<<left<<setw(15)<<"  Enter a Roman Numeral"<<endl;
	cout <<left<<setw(2)<<"3."<<left<<setw(15)<<"  Convert from Decimal to Roman"<<endl;
	cout <<left<<setw(2)<<"4."<<left<<setw(15)<<"  Convert from Roman to Decimal"<<endl;
	cout <<left<<setw(2)<<"5."<<left<<setw(15)<<"  Print the current Decimal number"<<endl;
	cout <<left<<setw(2)<<"6."<<left<<setw(15)<<"  Print the current Roman Numeral"<<endl;
	cout <<left<<setw(2)<<"7."<<left<<setw(15)<<"  Quit"<<endl;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//  File: Menu.cpp
//  Purpose: Converts a number enetered in Decimal to Roman Numeral and a 
//  Roman Numeral to a Decimal Number 
// ============================================================================
#include <iostream>
#include <iomanip>
#include <string>
#include "ClassRomanType.h"
using namespace std;
 
// function prototypes
void DisplayMenu();
int GetCommand(int command);
void RunChoice(int command, ClassRomanType& romanObject);
 
int main()
{
	int command=7;	// Holds which action the user chooses to make
	ClassRomanType	romanObject;	// Gives access to the class
 
	do{
		DisplayMenu();
		command = GetCommand(command);
		RunChoice(command, romanObject);
		cout<<"n--------------------------------------------------------------------n";
	}while(command!=7);
 
	cout<<"nBye!n";
 
	return 0;
}// End of main
 
void RunChoice(int command, ClassRomanType& romanObject)
{// Function: Execute the choice selected from the menu
 
	// declare private variables
	int decimalNumber=0;	// Holds decimal value
	char romanNumeral[150];	//Holds value of roman numeral
 
	// execute the desired choice
	cout <<"ntYou selected choice #"<<command<<" which will: ";
	switch(command)
	{
	case 1:
		cout << "Get Decimal Numbernn";
		cout <<"Enter a Decimal Number: ";
		cin >> decimalNumber;
		romanObject.GetDecimalNumber(decimalNumber);
		break;
	case 2:
		cout << "Get Roman Numeralnn";
		cout <<"nEnter a Roman Numeral: ";
		cin >> romanNumeral;
		romanObject.GetRomanNumeral(romanNumeral);
		break;
	case 3:
		cout << "Convert from Decimal to Romannn";
		romanObject.ConvertDecimalToRoman();
		cout<<"Running....nComplete!n";
		break;
	case 4:
		cout << "Convert from Roman to Decimalnn";
		romanObject.ConvertRomanToDecimal();
		cout<<"Running....nComplete!n";
		break;
	case 5:
		cout << "Print the current Decimal numbernn";
		cout<<"n The current Roman to Decimal Value is: "; 
		cout << romanObject.ReturnDecimalNumber()<<endl;
		break;
	case 6:
		cout << "Print the current Roman Numeralnn";
		cout<<"n The current Decimal to Roman Value is: "; 
		cout << romanObject.ReturnRomanNumber()<<endl;
		break;
	case 7:
		cout << "Quitnn";
		break;
	default:
		cout << "nError, you entered an invalid command!nPlease try again...";
		break;
	}
}//End of RunChoice
 
int GetCommand(int command)
{// Function: Gets choice from menu
	cout <<"nPlease enter a selection: ";
	cin>> command;
	return command;
}// End of GetCommand
 
void DisplayMenu()
{// Function: Displays menu
	cout <<"From the following menu:n"<<endl;
	cout <<left<<setw(2)<<"1."<<left<<setw(15)<<"  Enter a Decimal number"<<endl;
	cout <<left<<setw(2)<<"2."<<left<<setw(15)<<"  Enter a Roman Numeral"<<endl;
	cout <<left<<setw(2)<<"3."<<left<<setw(15)<<"  Convert from Decimal to Roman"<<endl;
	cout <<left<<setw(2)<<"4."<<left<<setw(15)<<"  Convert from Roman to Decimal"<<endl;
	cout <<left<<setw(2)<<"5."<<left<<setw(15)<<"  Print the current Decimal number"<<endl;
	cout <<left<<setw(2)<<"6."<<left<<setw(15)<<"  Print the current Roman Numeral"<<endl;
	cout <<left<<setw(2)<<"7."<<left<<setw(15)<<"  Quit"<<endl;
}// http://programmingnotes.org/

======== FILE #2 – ClassRomanType.h ========

Remember, you need to name the header file the same as the #include from the Menu.cpp file. This file contains the function declarations, but no implementation of those functions takes place here.





		
		
			File #2 - ClassRomanType.h
			
C++
			
			// ============================================================================
//  File:  ClassRomanType.h
//  Purpose:  Header file for Roman Numeral conversion. It contains all
//  declarations and prototypes for the class members to carry out the 
//  conversion
// ============================================================================
#include <string>
using namespace std;

class   ClassRomanType
{
public:
    ClassRomanType();
          /*   Function: constructor initializes class variables to "0"
               Precondition: none
               Postcondition: defines private variables */

	// member functions
    void GetDecimalNumber(int  decimalNumber);
          /*   Function: gets decimal number
			Precondition: none
			Postcondition: Gets arabic number from user */

    void GetRomanNumeral(char romanNumeral[]);
          /*   Function: gets roman numeral
			Precondition: none
			Postcondition: Gets roman numeral from user */

    void ConvertDecimalToRoman();
          /*   Function: converts decimal number to ronman numeral
			Precondition: arabic and roman numeral characters should be known
			Postcondition: Gets roman numeral from user */

    void ConvertRomanToDecimal();
          /*   Function: converts roman numeral to arabic number 
			Precondition: arabic and roman numeral characters should be known
			Postcondition: Gets decimal number from user */

    int ReturnDecimalNumber();
          /*   Function: displays converted decimal number 
			Precondition: the converted roman numeral to decimal number
			Postcondition: displays decimal number to user */

    string ReturnRomanNumber();
          /*   Function: displays converted roman numeral 
			Precondition: the converted decimal number to roman numeral
			Postcondition: displays roman numeral to user */

    ~ClassRomanType();
          /*   Function: destructor used to return memory to the system 
			Precondition: the converted decimal number to roman numeral
			Postcondition: none */

private:
	char	m_romanValue[150];  // An array holding the roman value within the class
	int	m_decimalValue;	// Holds the final output answer of the roman to decimal conversion
}; // http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//  File:  ClassRomanType.h
//  Purpose:  Header file for Roman Numeral conversion. It contains all
//  declarations and prototypes for the class members to carry out the 
//  conversion
// ============================================================================
#include <string>
using namespace std;
 
class   ClassRomanType
{
public:
    ClassRomanType();
          /*   Function: constructor initializes class variables to "0"
               Precondition: none
               Postcondition: defines private variables */
 
	// member functions
    void GetDecimalNumber(int  decimalNumber);
          /*   Function: gets decimal number
			Precondition: none
			Postcondition: Gets arabic number from user */
 
    void GetRomanNumeral(char romanNumeral[]);
          /*   Function: gets roman numeral
			Precondition: none
			Postcondition: Gets roman numeral from user */
 
    void ConvertDecimalToRoman();
          /*   Function: converts decimal number to ronman numeral
			Precondition: arabic and roman numeral characters should be known
			Postcondition: Gets roman numeral from user */
 
    void ConvertRomanToDecimal();
          /*   Function: converts roman numeral to arabic number 
			Precondition: arabic and roman numeral characters should be known
			Postcondition: Gets decimal number from user */
 
    int ReturnDecimalNumber();
          /*   Function: displays converted decimal number 
			Precondition: the converted roman numeral to decimal number
			Postcondition: displays decimal number to user */
 
    string ReturnRomanNumber();
          /*   Function: displays converted roman numeral 
			Precondition: the converted decimal number to roman numeral
			Postcondition: displays roman numeral to user */
 
    ~ClassRomanType();
          /*   Function: destructor used to return memory to the system 
			Precondition: the converted decimal number to roman numeral
			Postcondition: none */
 
private:
	char	m_romanValue[150];  // An array holding the roman value within the class
	int	m_decimalValue;	// Holds the final output answer of the roman to decimal conversion
}; // http://programmingnotes.org/

======== FILE #3 – RomanType.cpp ========

This is the function implementation file for the ClassRomanType.h class. This file can be named anything you wish as long as you #include “ClassRomanType.h”





		
		
			File #3 - RomanType.cpp
			
C++
			
			// ============================================================================
//  File:  RomanType.cpp
//  Purpose:  Contains the implementation of the class members for the 
//  roman numeral conversion
//  
//  *NOTE*: Uncomment cout statements to visualize whats happening
// ============================================================================
#include <iostream>
#include <string> 
#include <cstring>
#include "ClassRomanType.h"
using namespace std;

ClassRomanType::ClassRomanType()
{
	m_decimalValue=0;
	strcpy(m_romanValue,"Currently Undefined");
}// end of ClassRomanType

void ClassRomanType:: GetDecimalNumber(int decimalNumber)
{
	m_decimalValue = decimalNumber;
}// end of GetDecimalNumber

void ClassRomanType:: GetRomanNumeral(char romanNumeral[])
{
	strcpy(m_romanValue,romanNumeral);
}// end of GetRomanNumeral

void ClassRomanType:: ConvertDecimalToRoman()
{ 
	strcpy(m_romanValue,""); // erases any previous data
	int numericValue[]={1000,900,500,400,100,90,50,40,10,9,5,4,1,0};
	char *romanNumeral[]={"M","CM","D","CD","C","XC","L"
									,"XL","X","IX","V","IV","I",0};
	
	for (int x=0; numericValue[x] > 0; ++x)
	{
		//cout<<endl<<numericValue[x]<<endl;
		while (m_decimalValue >= numericValue[x])
		{
			//cout<<"current m_decimalValue = " <<m_decimalValue<<endl;
			//cout<<"current numericValue = "<<numericValue[x]<<endl<<endl;
			if(strlen(m_romanValue)==0)
			{
				strcpy(m_romanValue,romanNumeral[x]);
			}
			else
			{
				strcat(m_romanValue,romanNumeral[x]);
			}
			m_decimalValue  -= numericValue[x];
		}
	}
}// end of ConvertDecimalToRoman

void ClassRomanType:: ConvertRomanToDecimal()
{
	 int currentNumber = 0;	// Holds value of each letter numerical value
	 int previousNumber = 0; // Holds the numerical value being compared 
	 m_decimalValue=0; // Resets the current 'romanToDecimalValue' to zero

	 if(strcmp(m_romanValue,"Currently Undefined")!=0)
	 {
		 for (int counter = strlen(m_romanValue)-1; counter >= 0; counter--)
		 {
			 if ((m_romanValue[counter] == 'M') || (m_romanValue[counter] == 'm'))
			 {
				 currentNumber = 1000;
			 }
			 else if ((m_romanValue[counter] == 'D') || (m_romanValue[counter] == 'd'))
			 {
				 currentNumber = 500;
			 }
			 else if ((m_romanValue[counter] == 'C') || (m_romanValue[counter] == 'c'))
			 {
				 currentNumber = 100;
			 }
			 else if ((m_romanValue[counter] == 'L') || (m_romanValue[counter] == 'l'))
			 {
				 currentNumber = 50;
			 }
			 else if ((m_romanValue[counter] == 'X') || (m_romanValue[counter] == 'x'))
			 {
				 currentNumber = 10;
			 }
			 else if ((m_romanValue[counter] == 'V') || (m_romanValue[counter] == 'v'))
			 {
				 currentNumber = 5;
			 }  
			 else if ((m_romanValue[counter] == 'I') || (m_romanValue[counter] == 'i'))
			 {
				 currentNumber = 1;
			 }
			 else
			 {
				 currentNumber = 0;
			 }
			 //cout<<"previousNumber = " <<previousNumber<<endl;
			 //cout<<"currentNumber = " <<currentNumber<<endl;

			 if (previousNumber > currentNumber)
			 {
				 m_decimalValue -= currentNumber;
				 previousNumber = currentNumber;
			 }
			 else
			 {
				 m_decimalValue += currentNumber;
				 previousNumber = currentNumber;
			 }	
			 //cout<<"current m_decimalValue = " <<m_decimalValue<<endl<<endl;
		 }
	 }
}// end of ConvertRomanToDecimal

int ClassRomanType::ReturnDecimalNumber()
{
	return m_decimalValue;
}// end of ReturnDecimalNumber

string ClassRomanType::ReturnRomanNumber()
{
	return  m_romanValue;
}// end of ReturnRomanNumber

ClassRomanType::~ClassRomanType()
{
	m_decimalValue=0;
	strcpy(m_romanValue,"Currently Undefined");
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//  File:  RomanType.cpp
//  Purpose:  Contains the implementation of the class members for the 
//  roman numeral conversion
//  
//  *NOTE*: Uncomment cout statements to visualize whats happening
// ============================================================================
#include <iostream>
#include <string> 
#include <cstring>
#include "ClassRomanType.h"
using namespace std;
 
ClassRomanType::ClassRomanType()
{
	m_decimalValue=0;
	strcpy(m_romanValue,"Currently Undefined");
}// end of ClassRomanType
 
void ClassRomanType:: GetDecimalNumber(int decimalNumber)
{
	m_decimalValue = decimalNumber;
}// end of GetDecimalNumber
 
void ClassRomanType:: GetRomanNumeral(char romanNumeral[])
{
	strcpy(m_romanValue,romanNumeral);
}// end of GetRomanNumeral
 
void ClassRomanType:: ConvertDecimalToRoman()
{ 
	strcpy(m_romanValue,""); // erases any previous data
	int numericValue[]={1000,900,500,400,100,90,50,40,10,9,5,4,1,0};
	char *romanNumeral[]={"M","CM","D","CD","C","XC","L"
									,"XL","X","IX","V","IV","I",0};
	
	for (int x=0; numericValue[x] > 0; ++x)
	{
		//cout<<endl<<numericValue[x]<<endl;
		while (m_decimalValue >= numericValue[x])
		{
			//cout<<"current m_decimalValue = " <<m_decimalValue<<endl;
			//cout<<"current numericValue = "<<numericValue[x]<<endl<<endl;
			if(strlen(m_romanValue)==0)
			{
				strcpy(m_romanValue,romanNumeral[x]);
			}
			else
			{
				strcat(m_romanValue,romanNumeral[x]);
			}
			m_decimalValue  -= numericValue[x];
		}
	}
}// end of ConvertDecimalToRoman
 
void ClassRomanType:: ConvertRomanToDecimal()
{
	 int currentNumber = 0;	// Holds value of each letter numerical value
	 int previousNumber = 0; // Holds the numerical value being compared 
	 m_decimalValue=0; // Resets the current 'romanToDecimalValue' to zero
 
	 if(strcmp(m_romanValue,"Currently Undefined")!=0)
	 {
		 for (int counter = strlen(m_romanValue)-1; counter >= 0; counter--)
		 {
			 if ((m_romanValue[counter] == 'M') || (m_romanValue[counter] == 'm'))
			 {
				 currentNumber = 1000;
			 }
			 else if ((m_romanValue[counter] == 'D') || (m_romanValue[counter] == 'd'))
			 {
				 currentNumber = 500;
			 }
			 else if ((m_romanValue[counter] == 'C') || (m_romanValue[counter] == 'c'))
			 {
				 currentNumber = 100;
			 }
			 else if ((m_romanValue[counter] == 'L') || (m_romanValue[counter] == 'l'))
			 {
				 currentNumber = 50;
			 }
			 else if ((m_romanValue[counter] == 'X') || (m_romanValue[counter] == 'x'))
			 {
				 currentNumber = 10;
			 }
			 else if ((m_romanValue[counter] == 'V') || (m_romanValue[counter] == 'v'))
			 {
				 currentNumber = 5;
			 }  
			 else if ((m_romanValue[counter] == 'I') || (m_romanValue[counter] == 'i'))
			 {
				 currentNumber = 1;
			 }
			 else
			 {
				 currentNumber = 0;
			 }
			 //cout<<"previousNumber = " <<previousNumber<<endl;
			 //cout<<"currentNumber = " <<currentNumber<<endl;
 
			 if (previousNumber > currentNumber)
			 {
				 m_decimalValue -= currentNumber;
				 previousNumber = currentNumber;
			 }
			 else
			 {
				 m_decimalValue += currentNumber;
				 previousNumber = currentNumber;
			 }	
			 //cout<<"current m_decimalValue = " <<m_decimalValue<<endl<<endl;
		 }
	 }
}// end of ConvertRomanToDecimal
 
int ClassRomanType::ReturnDecimalNumber()
{
	return m_decimalValue;
}// end of ReturnDecimalNumber
 
string ClassRomanType::ReturnRomanNumber()
{
	return  m_romanValue;
}// end of ReturnRomanNumber
 
ClassRomanType::~ClassRomanType()
{
	m_decimalValue=0;
	strcpy(m_romanValue,"Currently Undefined");
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

From the following menu:
1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 9 You selected choice #9 which will: Error, you entered an invalid command! Please try again... -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 5 You selected choice #5 which will: Print the current Decimal number The current Roman to Decimal Value is: 0 -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 6 You selected choice #6 which will: Print the current Roman Numeral The current Decimal to Roman Value is: Currently Undefined -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 1 You selected choice #1 which will: Get Decimal Number Enter a Decimal Number: 1987 -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 5 You selected choice #5 which will: Print the current Decimal number The current Roman to Decimal Value is: 1987 -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 3 You selected choice #3 which will: Convert from Decimal to Roman Running.... Complete! -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 6 You selected choice #6 which will: Print the current Roman Numeral The current Decimal to Roman Value is: MCMLXXXVII -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 2 You selected choice #2 which will: Get Roman Numeral Enter a Roman Numeral: mMxiI -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 6 You selected choice #6 which will: Print the current Roman Numeral The current Decimal to Roman Value is: mMxiI -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 4 You selected choice #4 which will: Convert from Roman to Decimal Running.... Complete! -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 5 You selected choice #5 which will: Print the current Decimal number The current Roman to Decimal Value is: 2012 -------------------------------------------------------------------- From the following menu: 1. Enter a Decimal number 2. Enter a Roman Numeral 3. Convert from Decimal to Roman 4. Convert from Roman to Decimal 5. Print the current Decimal number 6. Print the current Roman Numeral 7. Quit Please enter a selection: 7
You selected choice #7 which will: Quit -------------------------------------------------------------------- Bye!

C++ || Snippet – Linked List Custom Template Stack Sample Code

April 09, 2012 admin No comments

This page will consist of sample code for a custom linked list template stack. This page differs from the previously highlighted array based template stack in that this version uses a singly linked list to store data rather than using an array.

Looking for sample code for a queue? Click here.

REQUIRED KNOWLEDGE FOR THIS SNIPPET

Structs Classes Template Classes - What Are They? Stacks LIFO - What Is It? #include < stack> Linked Lists - How To Use

This template class is a custom duplication of the Standard Template Library (STL) stack class. Whether you like building your own data structures, you simply do not like to use any inbuilt functions, opting to build everything yourself, or your homework requires you make your own data structure, this sample code is really useful. I feel its beneficial building functions such as this, that way you better understand the behind the scene processes.





		
		
			#include 'ClassStackListType.h'
			
C++
			
			// ============================================================================
//    Author: K Perkins
//    Date:   Apr 9, 2012
//    Taken From: http://programmingnotes.org/
//    File:  ClassStackListType.h
//    Description: This is a class which implements various functions
//          demonstrating the use of a stack. 
// ============================================================================
#include <iostream>         

template <class ItemType>
class StackListType
{
public:
    StackListType();
          /*   Function: constructor initializes class variables 
               Precondition: none
               Postcondition: defines private variables */
    bool IsEmpty();
          /*   Function: Determines whether the stack is empty
               Precondition: Stack has been initialized
               Postcondition: Function value = (stack is empty) */
    bool IsFull();
          /*   Function: Determines whether the stack is full
               Precondition: Stack has been initialized
               Postcondition: Function value = (stack is full) */
    int Size();
          /*   Function: Return the current size of the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is full) exception FullStack is thrown
                                   else newItem is at the top of the stack */
    void MakeEmpty();
          /*   Function: Empties the stack
               Precondition: Stack has been initialized
               Postcondition: Stack is empty */
    void Push(ItemType newItem);
          /*   Function: Adds newItem to the top of the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is full) exception FullStack is thrown
                                   else newItem is at the top of the stack */
    ItemType Pop();
          /*   Function: Returns & then removes top item from the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is empty) exception EmptyStack is thrown
                                   else top element has been removed from the stack */
    ItemType Top();
          /*   Function: Returns the top item from the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is empty) exception EmptyStack is thrown
                                   else top element has been removed from the stack */
    ~StackListType();
          /*   Function: destructor deallocates class variables 
               Precondition: none
               Postcondition: deallocates private variables */

private:
    struct NodeType
    {
          ItemType currentItem;  // Variable which hold all the incoming currentItem
          NodeType* next; // Creates a pointer that points to the next node in the list.
    };
    int size;          // Indicates the size of the stack	
    ItemType junk;
    NodeType* headPtr; // Creates a head pointer that will point to the begining of the list.
};

//=========================  Implementation  ================================//

template<class ItemType>
StackListType<ItemType>::StackListType()
{
    size = 0;
    headPtr = NULL;
}//     End of StackListType

template<class ItemType>
bool StackListType<ItemType>::IsEmpty()
{
    return (headPtr == NULL);
}//     End of IsEmpty

template<class ItemType>
bool StackListType<ItemType>::IsFull()
{    
    try
    {
        NodeType* tempPtr = new NodeType;
        delete tempPtr;
        return false;
    }
    catch(std::bad_alloc&)
    {
        return true;
    }
}//     End of IsFull

template<class ItemType>
int StackListType<ItemType>::Size()
{
    if(IsEmpty())
    {
        std::cout<<"nSTACK EMPTYn";
    }
    return size;
}//     End of Size

template<class ItemType>
void StackListType<ItemType>::MakeEmpty()
{
    size = 0;    
	
    if (!IsEmpty())
	{
        std::cout << "Destroying nodes ...n";

		while (!IsEmpty())
		{
			NodeType* tempPtr = headPtr;
			//std::cout << tempPtr-> currentItem << 'n';
			headPtr = headPtr-> next;
			delete tempPtr;
		}
	}     
}//     End of MakeEmpty

template<class ItemType>
void StackListType<ItemType>::Push(ItemType newItem)
{
    if(IsFull())
    {
        std::cout<<"nSTACK FULLn";
        return;
    }
    NodeType* tempPtr = new NodeType;
    tempPtr-> currentItem = newItem;
    tempPtr-> next = headPtr;
    headPtr = tempPtr;
    ++size;
}//     End of Push

template<class ItemType>
ItemType StackListType<ItemType>::Pop()
{
    if(IsEmpty())
    {
        std::cout<<"nSTACK EMPTYn";
        return junk;
    }
    else
    {  
        ItemType data = headPtr-> currentItem;  
        NodeType* tempPtr = headPtr;
        headPtr = headPtr-> next;
        delete tempPtr;
        --size;
        return data;
    }
}//     End of Pop

template<class ItemType>
ItemType StackListType<ItemType>::Top()
{
    if(IsEmpty())
    {
        std::cout<<"nSTACK EMPTYn";
        return junk;
    }
    else
    { 
        return headPtr-> currentItem;
    }
}//     End of Top

template<class ItemType>
StackListType<ItemType>::~StackListType()
{
    MakeEmpty();   
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: K Perkins
//    Date:   Apr 9, 2012
//    Taken From: http://programmingnotes.org/
//    File:  ClassStackListType.h
//    Description: This is a class which implements various functions
//          demonstrating the use of a stack. 
// ============================================================================
#include <iostream>         
 
template <class ItemType>
class StackListType
{
public:
    StackListType();
          /*   Function: constructor initializes class variables 
               Precondition: none
               Postcondition: defines private variables */
    bool IsEmpty();
          /*   Function: Determines whether the stack is empty
               Precondition: Stack has been initialized
               Postcondition: Function value = (stack is empty) */
    bool IsFull();
          /*   Function: Determines whether the stack is full
               Precondition: Stack has been initialized
               Postcondition: Function value = (stack is full) */
    int Size();
          /*   Function: Return the current size of the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is full) exception FullStack is thrown
                                   else newItem is at the top of the stack */
    void MakeEmpty();
          /*   Function: Empties the stack
               Precondition: Stack has been initialized
               Postcondition: Stack is empty */
    void Push(ItemType newItem);
          /*   Function: Adds newItem to the top of the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is full) exception FullStack is thrown
                                   else newItem is at the top of the stack */
    ItemType Pop();
          /*   Function: Returns & then removes top item from the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is empty) exception EmptyStack is thrown
                                   else top element has been removed from the stack */
    ItemType Top();
          /*   Function: Returns the top item from the stack
               Precondition: Stack has been initialized
               Postcondition: If (stack is empty) exception EmptyStack is thrown
                                   else top element has been removed from the stack */
    ~StackListType();
          /*   Function: destructor deallocates class variables 
               Precondition: none
               Postcondition: deallocates private variables */
 
private:
    struct NodeType
    {
          ItemType currentItem;  // Variable which hold all the incoming currentItem
          NodeType* next; // Creates a pointer that points to the next node in the list.
    };
    int size;          // Indicates the size of the stack	
    ItemType junk;
    NodeType* headPtr; // Creates a head pointer that will point to the begining of the list.
};
 
//=========================  Implementation  ================================//
 
template<class ItemType>
StackListType<ItemType>::StackListType()
{
    size = 0;
    headPtr = NULL;
}//     End of StackListType
 
template<class ItemType>
bool StackListType<ItemType>::IsEmpty()
{
    return (headPtr == NULL);
}//     End of IsEmpty
 
template<class ItemType>
bool StackListType<ItemType>::IsFull()
{    
    try
    {
        NodeType* tempPtr = new NodeType;
        delete tempPtr;
        return false;
    }
    catch(std::bad_alloc&)
    {
        return true;
    }
}//     End of IsFull
 
template<class ItemType>
int StackListType<ItemType>::Size()
{
    if(IsEmpty())
    {
        std::cout<<"nSTACK EMPTYn";
    }
    return size;
}//     End of Size
 
template<class ItemType>
void StackListType<ItemType>::MakeEmpty()
{
    size = 0;    
	
    if (!IsEmpty())
	{
        std::cout << "Destroying nodes ...n";
 
		while (!IsEmpty())
		{
			NodeType* tempPtr = headPtr;
			//std::cout << tempPtr-> currentItem << 'n';
			headPtr = headPtr-> next;
			delete tempPtr;
		}
	}     
}//     End of MakeEmpty
 
template<class ItemType>
void StackListType<ItemType>::Push(ItemType newItem)
{
    if(IsFull())
    {
        std::cout<<"nSTACK FULLn";
        return;
    }
    NodeType* tempPtr = new NodeType;
    tempPtr-> currentItem = newItem;
    tempPtr-> next = headPtr;
    headPtr = tempPtr;
    ++size;
}//     End of Push
 
template<class ItemType>
ItemType StackListType<ItemType>::Pop()
{
    if(IsEmpty())
    {
        std::cout<<"nSTACK EMPTYn";
        return junk;
    }
    else
    {  
        ItemType data = headPtr-> currentItem;  
        NodeType* tempPtr = headPtr;
        headPtr = headPtr-> next;
        delete tempPtr;
        --size;
        return data;
    }
}//     End of Pop
 
template<class ItemType>
ItemType StackListType<ItemType>::Top()
{
    if(IsEmpty())
    {
        std::cout<<"nSTACK EMPTYn";
        return junk;
    }
    else
    { 
        return headPtr-> currentItem;
    }
}//     End of Top
 
template<class ItemType>
StackListType<ItemType>::~StackListType()
{
    MakeEmpty();   
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

===== DEMONSTRATION HOW TO USE =====

Use of the above template class is the same as its STL counterpart. Here is a sample program demonstrating its use.





		
		
			How To Use #include 'ClassStackListType.h'
			
C++
			
			#include <iostream>
#include "ClassStackListType.h"
using namespace std;

int  main()
{    // declare variables
     StackListType<char> charStack;
     StackListType<int> intStack;
     StackListType<float> floatStack;
     
     // ------ Char Example ------//
     char charArry[]="My Programming Notes Is Awesome";
     int counter=0;
     while(charArry[counter]!='\0')
     {
          charStack.Push(charArry[counter]);
          ++counter;
     }
     cout<<"charStack has "<<charStack.Size()<<" items in itn"
     <<"and contains the text ""<<charArry<<"" backwards:n";
     while(!charStack.IsEmpty())
     {
          cout<<charStack.Pop();
     }
     cout<<endl;     
     
     // ------ Int Example ------//
     int intArry[]={1,22,3,46,5,66,7,8,1987};
     counter=0;
     while(counter<9)
     {
          intStack.Push(intArry[counter]);
          ++counter;
     }
     cout<<"nintStack has "<<intStack.Size()<<" items in it.n"
     <<"The sum of the numbers in the stack is: ";
     counter=0;
     while(!intStack.IsEmpty())
     {
          counter+=intStack.Pop();
     }
     cout<<counter<<endl;
     
     // ------ Float Example ------//
     float floatArry[]={41.6,2.8,43.9,4.4,19.87,6.23,7.787,68.99,9.6,81.540};
     float sum=0;
     counter=0;
     while(counter<10)
     {
          floatStack.Push(floatArry[counter]);
          ++counter;
     }
     cout<<"nfloatStack has "<<floatStack.Size()<<" items in it.n"
     <<"The sum of the numbers in the stack is: ";
     while(!floatStack.IsEmpty())
     {
          sum+=floatStack.Pop();
     }
     cout<<sum<<endl;     
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
#include "ClassStackListType.h"
using namespace std;
 
int  main()
{    // declare variables
     StackListType<char> charStack;
     StackListType<int> intStack;
     StackListType<float> floatStack;
     
     // ------ Char Example ------//
     char charArry[]="My Programming Notes Is Awesome";
     int counter=0;
     while(charArry[counter]!='\0')
     {
          charStack.Push(charArry[counter]);
          ++counter;
     }
     cout<<"charStack has "<<charStack.Size()<<" items in itn"
     <<"and contains the text ""<<charArry<<"" backwards:n";
     while(!charStack.IsEmpty())
     {
          cout<<charStack.Pop();
     }
     cout<<endl;     
     
     // ------ Int Example ------//
     int intArry[]={1,22,3,46,5,66,7,8,1987};
     counter=0;
     while(counter<9)
     {
          intStack.Push(intArry[counter]);
          ++counter;
     }
     cout<<"nintStack has "<<intStack.Size()<<" items in it.n"
     <<"The sum of the numbers in the stack is: ";
     counter=0;
     while(!intStack.IsEmpty())
     {
          counter+=intStack.Pop();
     }
     cout<<counter<<endl;
     
     // ------ Float Example ------//
     float floatArry[]={41.6,2.8,43.9,4.4,19.87,6.23,7.787,68.99,9.6,81.540};
     float sum=0;
     counter=0;
     while(counter<10)
     {
          floatStack.Push(floatArry[counter]);
          ++counter;
     }
     cout<<"nfloatStack has "<<floatStack.Size()<<" items in it.n"
     <<"The sum of the numbers in the stack is: ";
     while(!floatStack.IsEmpty())
     {
          sum+=floatStack.Pop();
     }
     cout<<sum<<endl;     
}// http://programmingnotes.org/

Once compiled, you should get this as your output

charStack has 31 items in it and contains the text "My Programming Notes Is Awesome" backwards: emosewA sI setoN gnimmargorP yM
intStack has 9 items in it. The sum of the numbers in the stack is: 2145
floatStack has 10 items in it. The sum of the numbers in the stack is: 286.717

C++ || Printing Various Patterns Using Nested Loops

April 05, 2012 admin 1 Comment

This page will demonstrate various programs which illustrates the use of nested loops to print selected patterns to the screen.

REQUIRED KNOWLEDGE FOR THIS PAGE

While Loops For Loops Using Nested Loops

The following are famous homework assignments which are usually presented in an entry level programming course.

There are a total of ten (10) different patterns on this page, which is broken up into sections. This page will list:

(4) methods of printing a triangle (4) methods of printing an upside down triangle (1) method which prints a square (1) method which prints a giant letter 'X'

======= PRINTING A TRIANGLE =======

This program prints a triangle shape to the screen.





		
		
			#1 - Printing A Triangle
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter=1;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this is the start of the nested loop.
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=0; x < counter; ++x)
		{
			cout<<"* ";
		}
		cout<<endl;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter=1;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this is the start of the nested loop.
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=0; x < counter; ++x)
		{
			cout<<"* ";
		}
		cout<<endl;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/

In the above example, the user has a choice of entering the number of rows which will be displayed to the screen

SAMPLE OUTPUT:

Enter a number: 9 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

======= PRINTING A TRIANGLE WITH NUMBERS =======

The following program uses the same concept as above, but this time instead of using stars “*”, numbers will be printed to the screen.





		
		
			#2 - Printing A Triangle With Numbers
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter=1;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop.
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=0; x < counter; ++x)
		{
			cout<<copy<<" ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter=1;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop.
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=0; x < counter; ++x)
		{
			cout<<copy<<" ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 9 8 8 7 7 7 6 6 6 6 5 5 5 5 5 4 4 4 4 4 4 3 3 3 3 3 3 3 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1

======= PRINTING A TRIANGLE WITH NUMBERS IN-ORDER =======

The following program uses the same concept as above, but this time instead of using stars “*”, numbers will be printed to the screen in-order.





		
		
			#3 - Printing A Triangle With Numbers
			
C++
			
			#include <iostream>
using namespace std;
 
int main()
{
        // declare variables
        int number=0;
        int counter=1;
        int copy=0;
        
        // get data from user
        cout<<"Enter a number: ";
        cin>>number;    
        
        // this is the start of the nested loop.
        // NOTE: many use two nested 'for' loops, but
        // sometimes its nice to switch things up
        while(counter <= number)
        {
                copy=number;
                for(int x=0; x < counter; ++x)
                {
                        cout<<copy-(counter-1)<<" ";
                        ++copy;
                }
                cout<<endl;
                ++counter;
        }
        
        return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
        // declare variables
        int number=0;
        int counter=1;
        int copy=0;
        
        // get data from user
        cout<<"Enter a number: ";
        cin>>number;    
        
        // this is the start of the nested loop.
        // NOTE: many use two nested 'for' loops, but
        // sometimes its nice to switch things up
        while(counter <= number)
        {
                copy=number;
                for(int x=0; x < counter; ++x)
                {
                        cout<<copy-(counter-1)<<" ";
                        ++copy;
                }
                cout<<endl;
                ++counter;
        }
        
        return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 9 8 9 7 8 9 6 7 8 9 5 6 7 8 9 4 5 6 7 8 9 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9

======= PRINTING A TRIANGLE WITH NUMBERS USING MULTIPLICATION =======

This example demonstrates another triangle, this time printing a multiplication table.





		
		
			#4 - Printing A Triangle - Multiplication
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter=1;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= counter; ++x)
		{
			cout<<number*x<<" ";
		}
		cout<<endl;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter=1;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= counter; ++x)
		{
			cout<<number*x<<" ";
		}
		cout<<endl;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 9 9 18 9 18 27 9 18 27 36 9 18 27 36 45 9 18 27 36 45 54 9 18 27 36 45 54 63 9 18 27 36 45 54 63 72 9 18 27 36 45 54 63 72 81

======= PRINTING AN UPSIDE-DOWN TRIANGLE =======

This program is similar to the first one, this time printing the triangle upside-down.





		
		
			#5 - Printing An Upside Down Triangle
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter=0;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= copy; ++x)
		{
			cout<<"* ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter=0;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= copy; ++x)
		{
			cout<<"* ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

======= PRINTING AN UPSIDE-DOWN TRIANGLE WITH NUMBERS =======

This program is similar to the second one, this time printing the triangle upside-down.





		
		
			#6 - Printing An Upside Down Triangle With Numbers
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter=1;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= copy; ++x)
		{
			cout<<copy<<" ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter=1;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= copy; ++x)
		{
			cout<<copy<<" ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 9 9 9 9 9 9 9 9 9 8 8 8 8 8 8 8 8 7 7 7 7 7 7 7 6 6 6 6 6 6 5 5 5 5 5 4 4 4 4 3 3 3 2 2 1

======= PRINTING AN UPSIDE-DOWN TRIANGLE WITH NUMBERS IN-ORDER =======

The following program uses the same concept as above, but this time instead of using stars “*”, numbers will be printed to the screen in-order.





		
		
			#7 - Printing A Triangle With Numbers
			
C++
			
			#include <iostream>
using namespace std;
 
int main()
{
        // declare variables
        int number=0;
        int counter=1;
        int copy=0;
        
        // get data from user
        cout<<"Enter a number: ";
        cin>>number;
        
        copy=number;    
        
        // this is the start of the nested loop.
        // NOTE: many use two nested 'for' loops, but
        // sometimes its nice to switch things up
        while(counter <= number)
        {               
                for(int x=counter; x <= copy; ++x)
                {
                        cout<<x<<" ";
                }
                cout<<endl;
                ++counter;
        }
        
        return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
        // declare variables
        int number=0;
        int counter=1;
        int copy=0;
        
        // get data from user
        cout<<"Enter a number: ";
        cin>>number;
        
        copy=number;    
        
        // this is the start of the nested loop.
        // NOTE: many use two nested 'for' loops, but
        // sometimes its nice to switch things up
        while(counter <= number)
        {               
                for(int x=counter; x <= copy; ++x)
                {
                        cout<<x<<" ";
                }
                cout<<endl;
                ++counter;
        }
        
        return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 1 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9 3 4 5 6 7 8 9 4 5 6 7 8 9 5 6 7 8 9 6 7 8 9 7 8 9 8 9 9

===== PRINTING AN UPSIDE-DOWN TRIANGLE WITH NUMBERS USING MULTIPLICATION =====

This program is similar to the third one, this time printing the triangle upside-down.





		
		
			#8 - Printing An Upside Down Triangle - Multiplication
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter=1;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= copy; ++x)
		{
			cout<<number*x<<" ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter=1;
	int copy=0;
	
	// get data from user
	cout<<"Enter a number: ";
	cin>>number;
	
	// this variable is just a copy
	// of the number that the user just entered
	// which will be used in the nested loop
	copy=number;
	
	// this is the start of the nested loop
	// NOTE: many use two nested 'for' loops, but
	// sometimes its nice to switch things up
	while(counter <= number)
	{
		for(int x=1; x <= copy; ++x)
		{
			cout<<number*x<<" ";
		}
		cout<<endl;
		--copy;
		++counter;
	}
	
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:

Enter a number: 9 9 18 27 36 45 54 63 72 81 9 18 27 36 45 54 63 72 9 18 27 36 45 54 63 9 18 27 36 45 54 9 18 27 36 45 9 18 27 36 9 18 27 9 18 9

======= PRINTING A SQUARE =======

This program prints a square to the screen.





		
		
			#9 - Printing A Square
			
C++
			
			#include <iostream>
using namespace std;

int main()
{
	// declare variables
	int row=0;
	int column=0;
	int number=0;
	
	cout<<"Enter the number of rows to be printed: ";
	cin >> number;
	
	row = number;
	
	// draw top 
	while (row > 0) 
	{
		cout<<"*";
		--row;
	}
	cout<<endl;
	
	row = number - 2;
	column = number;
	
	// draw middle
	while (row > 0)
	{
		while (column > 0)
		{
			if ((column == number) || (column == 1))
			{
				cout<<"*";
			}
			else
			{
				cout<<" ";
			}
			--column;
		}
		cout<<endl;
		column = number;
		--row;
	}
	
	row = number;
	
	// draw bottom 
	while (row > 0) 
	{
		cout<<"*";
		--row;
	}
	cout<<endl;
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
using namespace std;
 
int main()
{
	// declare variables
	int row=0;
	int column=0;
	int number=0;
	
	cout<<"Enter the number of rows to be printed: ";
	cin >> number;
	
	row = number;
	
	// draw top 
	while (row > 0) 
	{
		cout<<"*";
		--row;
	}
	cout<<endl;
	
	row = number - 2;
	column = number;
	
	// draw middle
	while (row > 0)
	{
		while (column > 0)
		{
			if ((column == number) || (column == 1))
			{
				cout<<"*";
			}
			else
			{
				cout<<" ";
			}
			--column;
		}
		cout<<endl;
		column = number;
		--row;
	}
	
	row = number;
	
	// draw bottom 
	while (row > 0) 
	{
		cout<<"*";
		--row;
	}
	cout<<endl;
	
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:





		
		
			Enter the number of rows to be printed: 9
*********
*       *
*       *
*       *
*       *
*       *
*       *
*       *
*********
			
				
					
				
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						Enter the number of rows to be printed: 9
*********
*       *
*       *
*       *
*       *
*       *
*       *
*       *
*********

======= PRINTING THE LETTER “X” =======

The final program for this page will print a giant letter “X” to the screen.





		
		
			#10 - Printing The Letter 'X'
			
C++
			
			#include <iostream>
#include <cstdlib>
using namespace std;

int main()
{
	// declare variables
	int number=0;
	int counter1=0;
	
	cout<<"Enter the size of the shape: ";
	cin >> number;
	
	// set 'counter1' equal to 'number'
	counter1=-number;

	// start of the nested loop
	while(counter1 <=number)
	{
		for (int counter2 = -number; counter2 <= number; ++counter2)
		{
			if (abs(counter1) == abs(counter2))
			{
				cout<<"x";
			}
			else
			{
				cout<<" ";
			}
		}
		++counter1;
		cout<<endl;
	}

	return 0;
}// http://programmingnotes.org/ 
			
				
					
				
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						#include <iostream>
#include <cstdlib>
using namespace std;
 
int main()
{
	// declare variables
	int number=0;
	int counter1=0;
	
	cout<<"Enter the size of the shape: ";
	cin >> number;
	
	// set 'counter1' equal to 'number'
	counter1=-number;
 
	// start of the nested loop
	while(counter1 <=number)
	{
		for (int counter2 = -number; counter2 <= number; ++counter2)
		{
			if (abs(counter1) == abs(counter2))
			{
				cout<<"x";
			}
			else
			{
				cout<<" ";
			}
		}
		++counter1;
		cout<<endl;
	}
 
	return 0;
}// http://programmingnotes.org/

SAMPLE OUTPUT:





		
		
			Enter the size of the shape: 9
x                 x
 x               x
  x             x
   x           x
    x         x
     x       x
      x     x
       x   x
        x x
         x
        x x
       x   x
      x     x
     x       x
    x         x
   x           x
  x             x
 x               x
x                 x
			
				
					
				
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						Enter the size of the shape: 9
x                 x
 x               x
  x             x
   x           x
    x         x
     x       x
      x     x
       x   x
        x x
         x
        x x
       x   x
      x     x
     x       x
    x         x
   x           x
  x             x
 x               x
x                 x

And there you have it. Simple shapes made possible in C++.

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

C++ || Savings Account Balance – Calculate The Balance Of A Savings Account At The End Of A Period

April 04, 2012 admin 8 Comments

Here is another actual homework assignment which was presented in an intro to programming class. The following program was a question taken from the book “Starting Out with C++: Early Objects (7th Edition),” chapter 5, problem #16.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

For Loops - How To Use Them Assignment Operators - What Are They? Setprecision - What Is It? Interest Rate

This program first prompts the user to enter the annual interest rate, starting balance, and the number of months which has passed since the account was established. Upon obtaining the information, a loop is then used to iterate through each month, performing the following:

• Ask the user for the amount deposited into the account during the month (positive values only). This amount is added to the balance.
• Ask the user for the amount withdrawn from the account during the month (positive values only). This is subtracted from the balance.
• Calculate the monthly interest. The monthly interest rate is the annual interest rate divided by 12. After each loop iteration, the monthly interest rate is multiplied by the current balance, which is then added to the total balance.

After the last iteration, the program displays the ending balance, the total amount of deposits, the total amount of withdrawals, and the total interest earned.

If a negative balance is calculated at any point, an erroneous message is displayed to the screen indicating that the account has been closed, and then the program terminates.





		
		
			Savings Account Balance
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   April 4, 2012
//    Taken From: http://programmingnotes.org/
//    File:  SavingsAccount.cpp
//    Description: Demonstrates how to calculate the balance of a savings 
//      account at the end of a period
// ============================================================================
#include <iostream>
#include <cstdlib>
#include <iomanip>
using namespace std;

int main()
{
	// declare variables
	double annInterestRate = 0;
	double startingBalance = 0;
	int monthsPassed = 0;
	double deposits = 0;
	double withdrawal = 0;	
	double totDeposits = 0;
	double totWithdrawal = 0;
	double totInterest = 0;
	double monthlyInterestRate = 0;
	double totBalance = 0;
	
	// obtain data from user
	cout<<"Enter the annual interest rate on the account (e.g .04): ";
	cin >> annInterestRate;
	
	cout<<"Enter the starting balance: $";
	cin >> startingBalance;
	
	cout<<"How many months have passed since the account was established? ";
	cin >> monthsPassed;
	
	// initialize variables with the required info
	totBalance = startingBalance;
	monthlyInterestRate = annInterestRate/12;	
	
	// use a loop to obtain more data from user
	for(int x=1; x <= monthsPassed; ++x)
	{
		cout<<"\nMonth #"<<x<<endl;
		
		cout<<"\tTotal deposits for this month: $";
		cin >> deposits;
		totDeposits += deposits;
		totBalance += deposits;
		
		cout<<"\tTotal withdrawal for this month: $";
		cin >> withdrawal;
		totWithdrawal += withdrawal;
		totBalance -= withdrawal;
		
		totInterest += (totBalance*monthlyInterestRate);
		totBalance += (totBalance*monthlyInterestRate);

		// check for negative values
		// end loop if the values are negative
		if(deposits < 0 || withdrawal < 0 || totBalance < 0)
		{
			cout<< "\nPlease enter positive numbers only!";
			cout<<"\nThe account has been closed..\n";
			exit(1);
		}
	}
	
	// display results 
	cout<<fixed<<setprecision(2);
	cout.fill('.');
	cout<<"\nEnding balance:"<<left<<setw(20)<<right<<setw(20)<<" $ "<<totBalance;
	cout<<"\nAmount of deposits:"<<left<<setw(20)<<right<<setw(16)<<" $ "<<totDeposits;
	cout<<"\nAmount of withdrawals:"<<left<<setw(20)<<right<<setw(13)<<" $ "<<totWithdrawal;
	cout<<"\nAmount of interest earned:"<<left<<setw(20)<<right<<setw(9)<<" $ "<<totInterest<<endl;	
	
	return 0;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   April 4, 2012
//    Taken From: http://programmingnotes.org/
//    File:  SavingsAccount.cpp
//    Description: Demonstrates how to calculate the balance of a savings 
//      account at the end of a period
// ============================================================================
#include <iostream>
#include <cstdlib>
#include <iomanip>
using namespace std;
 
int main()
{
	// declare variables
	double annInterestRate = 0;
	double startingBalance = 0;
	int monthsPassed = 0;
	double deposits = 0;
	double withdrawal = 0;	
	double totDeposits = 0;
	double totWithdrawal = 0;
	double totInterest = 0;
	double monthlyInterestRate = 0;
	double totBalance = 0;
	
	// obtain data from user
	cout<<"Enter the annual interest rate on the account (e.g .04): ";
	cin >> annInterestRate;
	
	cout<<"Enter the starting balance: $";
	cin >> startingBalance;
	
	cout<<"How many months have passed since the account was established? ";
	cin >> monthsPassed;
	
	// initialize variables with the required info
	totBalance = startingBalance;
	monthlyInterestRate = annInterestRate/12;	
	
	// use a loop to obtain more data from user
	for(int x=1; x <= monthsPassed; ++x)
	{
		cout<<"\nMonth #"<<x<<endl;
		
		cout<<"\tTotal deposits for this month: $";
		cin >> deposits;
		totDeposits += deposits;
		totBalance += deposits;
		
		cout<<"\tTotal withdrawal for this month: $";
		cin >> withdrawal;
		totWithdrawal += withdrawal;
		totBalance -= withdrawal;
		
		totInterest += (totBalance*monthlyInterestRate);
		totBalance += (totBalance*monthlyInterestRate);
 
		// check for negative values
		// end loop if the values are negative
		if(deposits < 0 || withdrawal < 0 || totBalance < 0)
		{
			cout<< "\nPlease enter positive numbers only!";
			cout<<"\nThe account has been closed..\n";
			exit(1);
		}
	}
	
	// display results 
	cout<<fixed<<setprecision(2);
	cout.fill('.');
	cout<<"\nEnding balance:"<<left<<setw(20)<<right<<setw(20)<<" $ "<<totBalance;
	cout<<"\nAmount of deposits:"<<left<<setw(20)<<right<<setw(16)<<" $ "<<totDeposits;
	cout<<"\nAmount of withdrawals:"<<left<<setw(20)<<right<<setw(13)<<" $ "<<totWithdrawal;
	cout<<"\nAmount of interest earned:"<<left<<setw(20)<<right<<setw(9)<<" $ "<<totInterest<<endl;	
	
	return 0;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output

Enter the annual interest rate on the account (e.g .04): .07 Enter the starting balance: $5000 How many months have passed since the account was established? 3
Month #1 Total deposits for this month: $500 Total withdrawal for this month: $120 Month #2 Total deposits for this month: $750 Total withdrawal for this month: $200 Month #3 Total deposits for this month: $500 Total withdrawal for this month: $100
Ending balance:................. $ 6433.47 Amount of deposits:............. $ 1750.00 Amount of withdrawals:.......... $ 420.00 Amount of interest earned:...... $ 103.47

C++ || “One Size Fits All” – BubbleSort Which Works For Integer, Float, & Char Arrays

April 03, 2012 admin No comments

Here is another sorting algorithm, which sorts data that is contained in an array. The difference between this method, and the previous methods of sorting data is that this method works with multiple data types, all in one function. So for example, if you wanted to sort an integer and a character array within the same program, the code demonstrated on this page has the ability to sort both data types, eliminating the need to make two separate sorting functions for the two different data types.

REQUIRED KNOWLEDGE FOR THIS PROGRAM

Integer Arrays Character Arrays BubbleSort Pointers Function Pointers - What Are They? Memcpy Sizeof Sizet Malloc





		
		
			BubbleSort - One Size Fits All
			
C++
			
			#include <iostream>
#include <cstdlib>
#include <cctype>
#include <iomanip>
#include <cstring>
#include <ctime>
using namespace std;

// function prototypes
void BubbleSort(void* list, size_t nelm, size_t size, int (*cmp) (const void*, const void*));
void Swap(void* a, void* b, size_t width);
int IntCompare (const void * a, const void * b);
int StrCompare(const void *a, const void *b);
int FloatCompare (const void * a, const void * b);

// constant variable for int arrays
const int NUM_INTS=14;

int main()
{
	// seed random number generator
	srand(time(NULL));

	// ===================    INT EXAMPLE    =================== //
	int intNumbers[100];
	int numInts=0;	

	// place random numbers into the array
	for(int x = 0; x < NUM_INTS; ++x)
	{
		intNumbers[x] =rand()%100+1;
	} 

	cout<<"Original values in the int array:n";
	// show original data to the user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(4) << intNumbers[x];
	}
	
	// this is the function call, which takes in an 
	// integer array for sorting purposes
	// NOTICE: the function "IntCompare" is being used as a parameter
	BubbleSort(intNumbers,NUM_INTS,sizeof(int),IntCompare);
	
	cout<<"nnThe sorted values in the int array:n";
	// display sorted array to user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(4) << intNumbers[x];
	}

	// creates a line seperator 
	cout << "n-----------------------------------------------"
	<<"----------------------------------------n";
	
	// ===================    FLOAT EXAMPLE    =================== //
	float floatNumbers[100];

	// place random numbers into the array
	for(int x = 0; x < NUM_INTS; ++x)
	{
		floatNumbers[x] =(rand()%100+1)+(0.5);
	} 
	
	cout<<"Original values in the float array:n";
	// show original array to user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(6) << floatNumbers[x];
	}
	
	// this is the function call, which takes in a
	// float array for sorting purposes
	// NOTICE: the function "FloatCompare" is being used as a parameter
	BubbleSort(floatNumbers,NUM_INTS,sizeof(float),FloatCompare);
	
	cout<<"nnThe sorted values in the float array:n";
	// show sorted array to user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(6) << floatNumbers[x];
	}
	
	// creates a line seperator 
	cout << "n-----------------------------------------------"
	<<"----------------------------------------n";

	// ===================    CHAR EXAMPLE    =================== //
	char* names[100]={"This", "Is","Random","Text","Brought","To",
							"You","By","My","Programming","Notes"};
	int numNames=11;	

	cout<<"Original values in the char array:n";
	// show original array to user
	for(int x=0; x<numNames; ++x)
	{
		cout << " " << names[x];
	}
	
	// this is the function call, which takes in a 
	// char array for sorting purposes
	// NOTICE: the function "StrCompare" is being used as a parameter
	BubbleSort(names,numNames,sizeof(char*),StrCompare);
	
	cout<<"nnThe sorted values in the char array:n";
	// show sorted array to user
	for(int x=0; x<numNames; ++x)
	{
		cout << " " << names[x];
	}				
	cout<<endl;

	return 0;
}// end of main

void BubbleSort(void* arry, size_t nelm, size_t size, int (*cmp) (const void*, const void*))
{// this function sorts the received array
	bool sorted = false;
	
	do{
		sorted = true;
		for(unsigned int x=0; x < nelm-1; ++x)
		{
			if(cmp((((char*)arry)+(x*size)), (((char*)arry)+((x+1)*size))) > 0)
			{
				Swap((((char*)arry)+((x)*size)), (((char*)arry)+((x+1)*size)),size);
				sorted=false;
			}
		}
		--nelm;
	}while(!sorted);
}// end of BubbleSort					

void Swap(void* a, void* b, size_t width)
{// this function swaps the values in the array
	void *tmp = malloc(width);
	memcpy(tmp, a, width);
	memcpy(a, b, width);
	memcpy(b, tmp, width);
	free(tmp);
}// end of Swap

int FloatCompare (const void * a, const void * b)
{// this function compares two float values together
	return (*(float*)a - *(float*)b);
}// end of FloatCompare

int IntCompare (const void * a, const void * b)
{// this function compares two int values together
	return (*(int*)a - *(int*)b);
}// end of IntCompare

int StrCompare(const void *a, const void *b)
{// this function compares two char values together
  return(strcmp(*(const char **)a, *(const char **)b));
}// http://programmingnotes.org/
			
				
					
				
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						#include <iostream>
#include <cstdlib>
#include <cctype>
#include <iomanip>
#include <cstring>
#include <ctime>
using namespace std;
 
// function prototypes
void BubbleSort(void* list, size_t nelm, size_t size, int (*cmp) (const void*, const void*));
void Swap(void* a, void* b, size_t width);
int IntCompare (const void * a, const void * b);
int StrCompare(const void *a, const void *b);
int FloatCompare (const void * a, const void * b);
 
// constant variable for int arrays
const int NUM_INTS=14;
 
int main()
{
	// seed random number generator
	srand(time(NULL));
 
	// ===================    INT EXAMPLE    =================== //
	int intNumbers[100];
	int numInts=0;	
 
	// place random numbers into the array
	for(int x = 0; x < NUM_INTS; ++x)
	{
		intNumbers[x] =rand()%100+1;
	} 
 
	cout<<"Original values in the int array:n";
	// show original data to the user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(4) << intNumbers[x];
	}
	
	// this is the function call, which takes in an 
	// integer array for sorting purposes
	// NOTICE: the function "IntCompare" is being used as a parameter
	BubbleSort(intNumbers,NUM_INTS,sizeof(int),IntCompare);
	
	cout<<"nnThe sorted values in the int array:n";
	// display sorted array to user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(4) << intNumbers[x];
	}
 
	// creates a line seperator 
	cout << "n-----------------------------------------------"
	<<"----------------------------------------n";
	
	// ===================    FLOAT EXAMPLE    =================== //
	float floatNumbers[100];
 
	// place random numbers into the array
	for(int x = 0; x < NUM_INTS; ++x)
	{
		floatNumbers[x] =(rand()%100+1)+(0.5);
	} 
	
	cout<<"Original values in the float array:n";
	// show original array to user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(6) << floatNumbers[x];
	}
	
	// this is the function call, which takes in a
	// float array for sorting purposes
	// NOTICE: the function "FloatCompare" is being used as a parameter
	BubbleSort(floatNumbers,NUM_INTS,sizeof(float),FloatCompare);
	
	cout<<"nnThe sorted values in the float array:n";
	// show sorted array to user
	for(int x=0; x<NUM_INTS; ++x)
	{
		cout << setw(6) << floatNumbers[x];
	}
	
	// creates a line seperator 
	cout << "n-----------------------------------------------"
	<<"----------------------------------------n";
 
	// ===================    CHAR EXAMPLE    =================== //
	char* names[100]={"This", "Is","Random","Text","Brought","To",
							"You","By","My","Programming","Notes"};
	int numNames=11;	
 
	cout<<"Original values in the char array:n";
	// show original array to user
	for(int x=0; x<numNames; ++x)
	{
		cout << " " << names[x];
	}
	
	// this is the function call, which takes in a 
	// char array for sorting purposes
	// NOTICE: the function "StrCompare" is being used as a parameter
	BubbleSort(names,numNames,sizeof(char*),StrCompare);
	
	cout<<"nnThe sorted values in the char array:n";
	// show sorted array to user
	for(int x=0; x<numNames; ++x)
	{
		cout << " " << names[x];
	}				
	cout<<endl;
 
	return 0;
}// end of main
 
void BubbleSort(void* arry, size_t nelm, size_t size, int (*cmp) (const void*, const void*))
{// this function sorts the received array
	bool sorted = false;
	
	do{
		sorted = true;
		for(unsigned int x=0; x < nelm-1; ++x)
		{
			if(cmp((((char*)arry)+(x*size)), (((char*)arry)+((x+1)*size))) > 0)
			{
				Swap((((char*)arry)+((x)*size)), (((char*)arry)+((x+1)*size)),size);
				sorted=false;
			}
		}
		--nelm;
	}while(!sorted);
}// end of BubbleSort					
 
void Swap(void* a, void* b, size_t width)
{// this function swaps the values in the array
	void *tmp = malloc(width);
	memcpy(tmp, a, width);
	memcpy(a, b, width);
	memcpy(b, tmp, width);
	free(tmp);
}// end of Swap
 
int FloatCompare (const void * a, const void * b)
{// this function compares two float values together
	return (*(float*)a - *(float*)b);
}// end of FloatCompare
 
int IntCompare (const void * a, const void * b)
{// this function compares two int values together
	return (*(int*)a - *(int*)b);
}// end of IntCompare
 
int StrCompare(const void *a, const void *b)
{// this function compares two char values together
  return(strcmp(*(const char **)a, *(const char **)b));
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Notice, the same function declaration is being used for all 3 different data types, with the only difference between each function call are the parameters which are being sent out.

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: The function works for all three data types)

Original values in the int array: 44 91 43 22 20 100 77 80 84 60 47 91 51 81
The sorted values in the int array: 20 22 43 44 47 51 60 77 80 81 84 91 91 100 --------------------------------------------------------------------------------------- Original values in the float array: 49.5 30.5 67.5 50.5 29.5 89.5 78.5 80.5 54.5 7.5 54.5 38.5 56.5 70.5 The sorted values in the float array: 7.5 29.5 30.5 38.5 49.5 50.5 54.5 54.5 56.5 67.5 70.5 78.5 80.5 89.5 --------------------------------------------------------------------------------------- Original values in the char array: This Is Random Text Brought To You By My Programming Notes
The sorted values in the char array: Brought By Is My Notes Programming Random Text This To You

C++ || Stack Based Postfix Evaluation (Single Digit)

March 24, 2012 admin No comments

This page consists of another homework assignment which was presented in a C++ Data Structures course. While the previously discussed program dealt with converting Infix expressions to Postfix, this program will demonstrate exactly how to evaluate them.

NOTE: Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

REQUIRED KNOWLEDGE FOR THIS PROGRAM

What Is Postfix? How To Convert Infix To Postfix Equations Stack Data Structure Cin.getline How To Evaluate Postfix Expressions The Order Of Operations #include "ClassStackType.h"

The title of this page is called – “Stack Based Postfix Evaluation (Single Digit).” Why “single digit?” The program demonstrated on this page has the ability to evaluate a postfix equation, but it only has the ability to evaluate single digit values. What do I mean by that? Consider the infix equation: 5+2. When that expression is converted to postfix, it will come out to be: 52+, and the answer will be 7 (5+2=7). But what if we have an equation like 12+2? When that expression is converted to postfix, it will come out to be: 122+. The postfix conversion is correct, but when you try to evaluate the expression, we do not know if the math operation should be 12+2 or 1+22, it can be read either way.

Question: So why is this program being displayed if it only works for single digits?
Answer: Because it demonstrates the process of evaluating postfix equations very well.

Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

Before we get into things, here is a helpful algorithm for evaluating a postfix expression in pseudo code:





		
		
			// An algorithm for postfix evaluation.
// For example,  (1 + 2) / (5 + 6) translates to  1 2 + 5 6 + /
// which equals the result of 0.272727
// Valid operands are single digits: 0-9
// Valid operators are: +, -, *, /, ^, $
// Highest precedence: ^, $
// Lowest precedence: +,-
// the operators ')' and '('never goes on stack.

double EvaluatePostfix(string postfix)
{
  while there is input
  {
    if input is a number
        push current number on stack
    else if input is a math operator and stack is not empty
        set operand2 to the top of the operand stack
            pop the stack
        set operand1 to the top of the operand stack
            pop the stack
        apply the math operation that represents to operand1 and operand2
            push the result onto the stack
    else error
  }
  // When the loop is finished, the operand stack will contain one item,
  // the result of evaluating the expression
  pop the stack
  return the answer to the caller
}// http://programmingnotes.org/
			
				
					
				
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						// An algorithm for postfix evaluation.
// For example,  (1 + 2) / (5 + 6) translates to  1 2 + 5 6 + /
// which equals the result of 0.272727
// Valid operands are single digits: 0-9
// Valid operators are: +, -, *, /, ^, $
// Highest precedence: ^, $
// Lowest precedence: +,-
// the operators ')' and '('never goes on stack.
 
double EvaluatePostfix(string postfix)
{
  while there is input
  {
    if input is a number
        push current number on stack
    else if input is a math operator and stack is not empty
        set operand2 to the top of the operand stack
            pop the stack
        set operand1 to the top of the operand stack
            pop the stack
        apply the math operation that represents to operand1 and operand2
            push the result onto the stack
    else error
  }
  // When the loop is finished, the operand stack will contain one item,
  // the result of evaluating the expression
  pop the stack
  return the answer to the caller
}// http://programmingnotes.org/

Once you understand the process of converting from infix to postfix, adding the ability to evaluate multiple digits within this program should be doable.

======= POSTFIX EVALUATION =======

This program uses a custom template.h class. To obtain the code for that class, click here.





		
		
			Postfix Evaluation (Single Digit)
			
C++
			
			// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Mar 24, 2012
//    Taken From: http://programmingnotes.org/
//    File:  PostfixEvaluation.cpp
//    Description: Demonstrate the use of a stack based postfix evaluation.
// ============================================================================
#include <iostream>
#include <cstdlib>
#include <cmath>
#include "ClassStackType.h"
using namespace std;

// function prototypes
void DisplayDirections();
double EvaluatePostfix(char* postfix);
bool IsMathOperator(char token);
double DoMath(double op1, double op2, char token);

int main()
{
     // declare variables
     char expression[50]; // array holding the postfix data
     double answer = 0;

     // display directions to user
     DisplayDirections();

     // get data from user
     cout<<"\nPlease enter a postfix expression: ";
     cin.getline(expression, sizeof(expression));

     cout <<"\nThe postfix expression = "<<expression<<endl;

     cout<<"\nCalculations:\n";

     answer = EvaluatePostfix(expression);

     cout<<"\nFinal answer = "<<answer<<endl;

     return 0;
}// end of main

void DisplayDirections()
{
     cout << "\n==== Postfix Evaluation ====\n"
         <<"\nMath Operators:\n"
         <<"+ || Addition\n"
         <<"- || Subtraction\n"
         <<"* || Multiplication\n"
         <<"/ || Division\n"
         <<"% || Modulus\n"
         <<"^ || Power\n"
         <<"$ || Square Rootn\n"
         <<"Sample Postfix Equation: 45^14*232+$2-/12%24*/* \n";
}// end of DisplayDirections

double EvaluatePostfix(char* postfix)
{
    // declare function variables
    int counter = 0;
    int currentNum = 0;
    char token = 'a';
    double op1 = 0;
    double op2 = 0;
    double answer = 0;
    StackType<double> doubleStack;

    // loop thru array until there is no more data
    while(postfix[counter] != '\0')
    {
        // push numbers onto the stack
        if(isdigit(postfix[counter]))
        {
            currentNum = postfix[counter] - '0';
            doubleStack.Push(currentNum);
        }
        else if(isspace(postfix[counter]))
        {
            // DO NOTHING
        }
        // if expression is a math operator, pop numbers from stack
        // & send the popped numbers to the 'DoMath' function
        else if((IsMathOperator(postfix[counter])) && (!doubleStack.IsEmpty()))
        {
            token = postfix[counter];

            // if expression is square root operation
            // only pop stack once
            if(token == '$')
            {
                op2 = 0;
                op1 = doubleStack.Top();
                doubleStack.Pop();

                answer = DoMath(op1,op2,token);
                doubleStack.Push(answer);
            }
            else
            {
                op2 = doubleStack.Top();
                doubleStack.Pop();
                op1 = doubleStack.Top();
                doubleStack.Pop();

                answer = DoMath(op1,op2,token);
                doubleStack.Push(answer);
            }
        }
        else
        {
            cout<<"\nINVALID INPUT\n";
            exit(1);
        }
        ++counter;
    }
    // pop the final answer from the stack, and return to main
    answer = doubleStack.Top();
    doubleStack.Pop();

    return answer;
}// end of EvaluatePostfix

bool IsMathOperator(char token)
{// this function checks if operand is a math operator
     switch(token)
     {
        case '+':
            return true;
            break;
        case '-':
            return true;
            break;
        case '*':
            return true;
            break;
        case '/':
            return true;
            break;
        case '%':
            return true;
            break;
        case '^':
            return true;
            break;
        case '$':
            return true;
            break;
        default:
            return false;
            break;
     }
}// end of IsMathOperator

double DoMath(double op1, double op2, char token)
{// this function carries out the actual math process
    double ans = 0;
    switch(token)
    {
        case '+':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 + op2;
            break;
        case '-':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 - op2;
            break;
        case '*':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 * op2;
            break;
        case '/':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 / op2;
            break;
        case '%':
            cout<<op1<<token<<op2<<" = ";
            ans = (int)op1 % (int)op2;
            break;
        case '^':
            cout<<op1<<token<<op2<<" = ";
            ans = pow(op1, op2);
            break;
        case '$':
            cout<<char(251)<<op1<<" = ";
            ans = sqrt(op1);
            break;
        default:
            ans = 0;
            break;
    }
    cout<<ans<<endl;
    return ans;
}// http://programmingnotes.org/
			
				
					
				
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						// ============================================================================
//    Author: Kenneth Perkins
//    Date:   Mar 24, 2012
//    Taken From: http://programmingnotes.org/
//    File:  PostfixEvaluation.cpp
//    Description: Demonstrate the use of a stack based postfix evaluation.
// ============================================================================
#include <iostream>
#include <cstdlib>
#include <cmath>
#include "ClassStackType.h"
using namespace std;
 
// function prototypes
void DisplayDirections();
double EvaluatePostfix(char* postfix);
bool IsMathOperator(char token);
double DoMath(double op1, double op2, char token);
 
int main()
{
     // declare variables
     char expression[50]; // array holding the postfix data
     double answer = 0;
 
     // display directions to user
     DisplayDirections();
 
     // get data from user
     cout<<"\nPlease enter a postfix expression: ";
     cin.getline(expression, sizeof(expression));
 
     cout <<"\nThe postfix expression = "<<expression<<endl;
 
     cout<<"\nCalculations:\n";
 
     answer = EvaluatePostfix(expression);
 
     cout<<"\nFinal answer = "<<answer<<endl;
 
     return 0;
}// end of main
 
void DisplayDirections()
{
     cout << "\n==== Postfix Evaluation ====\n"
         <<"\nMath Operators:\n"
         <<"+ || Addition\n"
         <<"- || Subtraction\n"
         <<"* || Multiplication\n"
         <<"/ || Division\n"
         <<"% || Modulus\n"
         <<"^ || Power\n"
         <<"$ || Square Rootn\n"
         <<"Sample Postfix Equation: 45^14*232+$2-/12%24*/* \n";
}// end of DisplayDirections
 
double EvaluatePostfix(char* postfix)
{
    // declare function variables
    int counter = 0;
    int currentNum = 0;
    char token = 'a';
    double op1 = 0;
    double op2 = 0;
    double answer = 0;
    StackType<double> doubleStack;
 
    // loop thru array until there is no more data
    while(postfix[counter] != '\0')
    {
        // push numbers onto the stack
        if(isdigit(postfix[counter]))
        {
            currentNum = postfix[counter] - '0';
            doubleStack.Push(currentNum);
        }
        else if(isspace(postfix[counter]))
        {
            // DO NOTHING
        }
        // if expression is a math operator, pop numbers from stack
        // & send the popped numbers to the 'DoMath' function
        else if((IsMathOperator(postfix[counter])) && (!doubleStack.IsEmpty()))
        {
            token = postfix[counter];
 
            // if expression is square root operation
            // only pop stack once
            if(token == '$')
            {
                op2 = 0;
                op1 = doubleStack.Top();
                doubleStack.Pop();
 
                answer = DoMath(op1,op2,token);
                doubleStack.Push(answer);
            }
            else
            {
                op2 = doubleStack.Top();
                doubleStack.Pop();
                op1 = doubleStack.Top();
                doubleStack.Pop();
 
                answer = DoMath(op1,op2,token);
                doubleStack.Push(answer);
            }
        }
        else
        {
            cout<<"\nINVALID INPUT\n";
            exit(1);
        }
        ++counter;
    }
    // pop the final answer from the stack, and return to main
    answer = doubleStack.Top();
    doubleStack.Pop();
 
    return answer;
}// end of EvaluatePostfix
 
bool IsMathOperator(char token)
{// this function checks if operand is a math operator
     switch(token)
     {
        case '+':
            return true;
            break;
        case '-':
            return true;
            break;
        case '*':
            return true;
            break;
        case '/':
            return true;
            break;
        case '%':
            return true;
            break;
        case '^':
            return true;
            break;
        case '$':
            return true;
            break;
        default:
            return false;
            break;
     }
}// end of IsMathOperator
 
double DoMath(double op1, double op2, char token)
{// this function carries out the actual math process
    double ans = 0;
    switch(token)
    {
        case '+':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 + op2;
            break;
        case '-':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 - op2;
            break;
        case '*':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 * op2;
            break;
        case '/':
            cout<<op1<<token<<op2<<" = ";
            ans = op1 / op2;
            break;
        case '%':
            cout<<op1<<token<<op2<<" = ";
            ans = (int)op1 % (int)op2;
            break;
        case '^':
            cout<<op1<<token<<op2<<" = ";
            ans = pow(op1, op2);
            break;
        case '$':
            cout<<char(251)<<op1<<" = ";
            ans = sqrt(op1);
            break;
        default:
            ans = 0;
            break;
    }
    cout<<ans<<endl;
    return ans;
}// http://programmingnotes.org/

QUICK NOTES:
The highlighted lines are sections of interest to look out for.

Want to convert & evaluate multi digit, decimal, and negative numbers? Click here!

The code is heavily commented, so no further insight is necessary. If you have any questions, feel free to leave a comment below.

Once compiled, you should get this as your output
(Note: the code was compile three separate times to display different output)

====== RUN 1 ======
==== Postfix Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root Sample Postfix Equation: 45^14*232+$2-/12%24*/* Please enter a postfix expression: 1 2 + 5 6 + / The postfix expression = 1 2 + 5 6 + / Calculations: 1+2 = 3 5+6 = 11 3/11 = 0.272727 Final answer = 0.272727 ====== RUN 2 ====== ==== Postfix Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root Sample Postfix Equation: 45^14*232+$2-/12%24*/* Please enter a postfix expression: 35*76^+ The postfix expression = 35*76^+ Calculations: 3*5 = 15 7^6 = 117649 15+117649 = 117664 Final answer = 117664 ====== RUN 3 ====== ==== Postfix Evaluation ==== Math Operators: + || Addition - || Subtraction * || Multiplication / || Division % || Modulus ^ || Power $ || Square Root Sample Postfix Equation: 45^14*232+$2-/12%24*/* Please enter a postfix expression: 45^4*32+$2-/12%24*/* The postfix expression = 45^4*32+$2-/12%24*/*
Calculations: 4^5 = 1024 1024*4 = 4096 3+2 = 5 √5 = 2.23607 2.23607-2 = 0.236068 4096/0.236068 = 17350.9 1%2 = 1 2*4 = 8 1/8 = 0.125 17350.9*0.125 = 2168.87 Final answer = 2168.87

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