Convert Celsius to Fahrenheit
The code has been modified slightly and now uploaded to the site.

21.cpp
#include <iostream>
using namespace std;
int main(){
double celsius;
double fahrenheit;
std::cout << "Enter a degree in Celsius: \n";
std::cin >> celsius;
fahrenheit = (9 / 5.0) * celsius + 32;
std::cout << celsius << " Celsius is " << fahrenheit << " Fahrenheit";
}