I'm having trouble with creating a program that calculates the greatest common divisor between two numbers. I would greatly appreciate some help.

Code:#include <iostream> using std::cout; using std::cin; using std::endl; double gcd ( int x, int y ); int main() { int a; int b; // allow the five sets of numbers to be input for ( int j = 1; j <= 5; ++j ) { cout << "Enter two integers: "; cin >> a >> b; cout << "The greatest common divisor of " << a << " and " << b << " is " << gcd ( a, b ) << "\n\n"; } // end for return 0; } // end main // function gcd definition double gcd( int x, int y ) { int greatest = 1; for ( int i = 2; i <= ( ( x < y ) ? x : y ); ++i ); if 0 = ( x % i ) + ( y % 1 ); greatest = i; return greatest; } // end function gcd