I have an unexpected error, does division work differently in C++?

Hello All, I was working on an exercise provided in this lesson:


and I tried to make a Fahrenheit to Celsius converter. My code is as follows:

#include <iostream> int main() { std::cout << "Temperature Converter \n \n"; std::cout << "Temperature in Farenheit: "; int tempf = 0; std::cin >> tempf; std::cout << "\n"; double tempc = (tempf - 32) * (5 / 9); std::cout << "The temperature in Celcius is: " << tempc << " \n"; }

I would put in a temperature in Fahrenheit and it would always give me 0 when it returned the Celsius value. I figured out that it was a problem with the parenthesis around the 5/9, but I don’t know why. Does division work in a weird way in C++?


See Issue #1 in the following post regarding integer division:


std::cout << 5 / 9 << "\n";  
// 0
std::cout << 5.0 / 9 << "\n";
// 0.555556

Also, if you want to restrict user to only enter integer values for Fahrenheit, then int tempf = 0; works.

But, if you want to allow the user to enter decimal values, then your declaration should be double tempf;

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