#include <iostream>
#include <algorithm>

unsigned gcd_rec(unsigned a, unsigned b)
{
    if (b == 0) return a;

    return gcd_rec(b, a % b);
}

unsigned gcd(unsigned a, unsigned b)
{
    if (a < b) std::swap(a, b);

    while (b) {
        int tmp = b;
        b = a % b;
        a = tmp;
    }

    return a;
}

int main(void)
{
    unsigned a, b;

    std::cout << "a = ";
    std::cin >> a;

    std::cout << "b = ";
    std::cin >> b;

    std::cout << "gcd(" << a << ", " << b << ") = " << gcd_rec(a, b) << std::endl;
    std::cout << "gcd(" << a << ", " << b << ") = " << gcd(a, b) << std::endl;
    
    return 0;
}