[solano]

I just started learning C++ last week, and after reading some of the C++ for dummies and writing the fahrenheit to celsius program, I thought I'd try to make something different.

The purpose of the program is to first enter a value, then enter another value and at the end the program will display the second value as a percentage of the first value. So basically a percentage calculator.

Here is the code:

#include <iostream>
#include <cstdio>
#include <cstdlib>

using namespace std;

int main(int nNumberofArgs, char* pszArgs[])

{
// Enter original value and define this variable as "original"
int original;
cout <<"Please enter original value:";
cin >> original;

// Enter value of change
int change;
cout <<"Please enter change:";
cin >> change;

// Calculate change fraction
int fraction;
fraction = change / original;

// Define constant
int constant;
constant = 100;


// Calculate percentage
int percentage;
percentage = fraction * constant;

// Display percentage change
cout <<"Percentage change is:";
cout << percentage << 
cout <<"%";
cout << endl;



// Wait for user 
system ("PAUSE");
return 0;

}

Do I need to use a different type of variable? Because the output is "00x4433c4%".

Thank you

[alias120]

I would suggest reading up on different Data Types. How do you define an integer? Are integers ever composed of non-whole numbers? Will an integer give you the output you seek?

http://www.cplusplus...rial/variables/

This post has been edited by alias120: 23 July 2012 - 12:03 PM

[jimblumberg]

What are you trying to print on this line?

cout << percentage << 

What is the purpose of the second insertion operator<<?

Also beware of using integer math when doing division. Remember integers have no fractions and any fractional part is truncated. Therefore something like 1/2 would evaluate to zero.



Jim

[Skydiver]

Yes. Good advice reading about data types.

To fix the hexadecimal number being printed, though, you need to change line 35 to cout << percentage;.

The trailing "<<" is taking the address of cout on the next line and printing it out.

[solano]

Thank you for quick replies. I will read up on different data types and whole numbers. Btw it's not a serious project, I'm only doing it to learn and that is exactly what you guys have helped me do.

[solano]

jimblumberg, on 23 July 2012 - 11:41 AM, said:

What are you trying to print on this line?

cout << percentage << 

What is the purpose of the second insertion operator<<?

Also beware of using integer math when doing division. Remember integers have no fractions and any fractional part is truncated. Therefore something like 1/2 would evaluate to zero.



Jim

I want it to display what value is stored in the integer "percentage", which I was hoping would be whatever is calculated from the formula earlier on in the code..

[solano]

btw I removed the << on line 35 and added the ;, as well as changing all the variables from int to double, and now it works! My first working program wuhu!

[Skydiver]

Congratulations!!!

[solano]

Skydiver, on 23 July 2012 - 03:03 PM, said:

Congratulations!!!

Thank you