HW problem. pretty sure its an easy mistake...cant find it tho.

[fmunoz314]

So this program will convert a temperature to either celcius or fahrenheit depending on if the user type a c or f. Works fine if i type c and a number but when i type f and a number i keep getting zero. Not sure why.I think the problem is somewhere in *float celcius (float)* but cant find it. I feel like its a simple mistake but i cant see it. :/ Thanks guys!

//****************************************************************************
// This program will convert a temperature to either celcius or fahrenheit 
// depending on if the user type a c or f.
//****************************************************************************

#include <iostream>
using namespace std;											
float fahrenheit(float);												// function prototype for fahrenheit
float celsius(float);													// function prototype for celcius

int main()
{	
	  float temperature;
      char choice;
   
      cout<< "Enter an F or a C and a number to be converted: ";
      cin>> choice >> temperature;
          
      if (choice=='f' || choice=='F')																				// If they choose F
	  {
         cout<< temperature << " degrees in Fahrenheit in Celcius is: " << celsius(temperature) << endl;
      }
      else if (choice=='c' || choice=='C')																			// If they choose C				
	  {
         cout<< temperature << " degrees in Celcius in Fahrenheit is: " << fahrenheit(temperature) << endl;
      }
	  else
		  cout<< "You have entered an invalid letter or you have entered them in the wrong order."<< endl;			// If they make a mistake

	system ("pause");
		return 0;

}

//**********************************************************************************************************************************
//**********************************************************************************************************************************
       
   float fahrenheit (float temp)
   {  
		return ((9/5*temp)+(32));
   }

//**********************************************************************************************************************************
//**********************************************************************************************************************************

   float celsius (float temp)
   {
		return ((temp-32)*(5/9));
   }

[germanchocolate]

Try doing using this instead:

return (temp - 32) * 5/9;

[fg109]

It's because he's doing integer division. Any integer divided by another integer will always result in an integer. Digits after the decimal are truncated. That means 5/9 is equal to zero. Solve it by casting at least one of the numbers as a float.

[fmunoz314]

wow! Thanks fg109! i knew it was something simple. Thanks a lot!!