#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <list>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <cmath>
#include <utility>
#include <sstream>
#include <queue>
#include <queue>

using namespace std;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

  int a, b, c, d;
  cin >> a >> b >> c >> d;

  int num = -1;
  if (a != 0) {
    num = c / a;
  }
  if (b != 0) {
    int num2 = d / b;
    if (num == -1) {
      num = num2;
    } else if (num2 < num) {
      num = num2;
    }
  }

  cout << num << endl;

  return 0;
}