C++: Greatest Common Divisor "GCD" (function)

#include <iostream.h>

int GCD(int a, int b)

{

    while( 1 )

    {

        a = a % b;

        if( a == 0 )

            return b;

        b = b % a;

        if( b == 0 )

            return a;

    }

}

int main()

{

    int x, y;

    cout << "This program allows calculating the GCD\n";

    cout << "Value 1: ";

    cin >> x;

    cout << "Value 2: ";

    cin >> y;

    cout << "\nThe Greatest Common Divisor of "

         << x << " and " << y << " is " << GCD(x, y) << endl;  

    return 0;

}