SOURCE #3

#include <iostream>

unsigned long long nod(unsigned long long, unsigned long long);

int main()
{
    unsigned long long a, b, w, h, wh_nod;

    std::cin >> a;
    std::cin >> b;
    std::cin >> w;
    std::cin >> h;

    wh_nod = nod(w, h);

    w /= wh_nod;
    h /= wh_nod;

    a /= w;
    b /= h;

    std::cout << (a < b ? a : b);

    return 0;
}

unsigned long long nod(unsigned long long a, unsigned long long b)
{
    while (a && b)
        if (a >= b)
            a %= b;
        else
            b %= a;

    return a | b;
}