# Programming Fundamentals/Functions/C++

## functions.cpp

```// This program asks the user for a Fahrenheit temperature,
// converts the given temperature to Celsius,
// and displays the results.
//
// References:
//     https://www.mathsisfun.com/temperature-conversion.html
//     https://en.wikibooks.org/wiki/C%2B%2B_Programming

#include <iostream>

using namespace std;

double getFahrenheit();
double calculateCelsius(double);
void displayResult(double, double);

int main() {
double fahrenheit;
double celsius;

fahrenheit = getFahrenheit();
celsius = calculateCelsius(fahrenheit);
displayResult(fahrenheit, celsius);

return 0;
}

double getFahrenheit() {
double fahrenheit;

cout << "Enter Fahrenheit temperature:" << endl;
cin >> fahrenheit;

return fahrenheit;
}

double calculateCelsius(double fahrenheit) {
double celsius;

celsius = (fahrenheit - 32) * 5 / 9;

return celsius;
}

void displayResult(double fahrenheit, double celsius) {
cout << fahrenheit << "° Fahrenheit is " << celsius << "° Celsius" << endl;
}
```

## Try It

Copy and paste the code above into one of the following free online development environments or use your own C++ compiler / interpreter / IDE.