#include <iostream>
 
using namespace std;
 
int nod(int a, int b){
    if (a <= 0 || b <= 0)
        return 0;
    cout << "OK\n";
    int c = 0;
    while(b > 0){
		cout << a << " " << b << "\n";
        c = a % b;
        a = b;
		b = c;
    }
    return a;
}
int main()
{
    cout << "Result: " << nod(9,15) << "\n";
    return 0;
}