#include <bits/stdc++.h>
using namespace std;
long long gcd(long long a, long long b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
int main() {
  long long a, b, x, y, m;
  cin >> a >> b >> x >> y;
  m = gcd(x, y);
  x = x / m;
  y = y / m;
  cout << min(a / x, b / y);
}
