#include <bits/stdc++.h>
using namespace std;

long f(long a, long b, long c, long v) {
  vector<long> DP(v + 1, 1e9);
  DP.at(0) = 0;
  for (auto x : {a, b, c}) {
    for (long i = 0; i < v + 1; i++) {
      if (DP.at(i) != 1e9) if (i + x < v + 1) DP.at(i + x) = min(DP.at(i + x), DP.at(i) + 1);
    }
  }
  return DP.at(v);
}

int main() {
  vector<long> V(4);
  for (long i = 0; i < 4; i++) cin >> V.at(i);
  long ans = LONG_MAX;
  for (long a = 1; a <= 30; a++) {
    for (long b = 1; b <= 30; b++) {
      for (long c = 1; c <= 30; c++) {
        long tmp = 0;
        for (auto v : V) tmp += f(a, b, c, v);
        ans = min(ans, tmp);
      }
    }
  }
  cout << ans << "\n";
}