What will be the output of the following C++ code?

#include <iostream>
using namespace std;
int gcd (int a, int b)
{
    int temp;
    while (b != 0) 
    {
        temp = a % b;
        a = b;
        b = temp;
    }
    return(a);
}
int main ()
{
    int x = 15, y = 25;
    cout << gcd(x, y);
    return(0);
}