#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;

ll Aw, Ab, Bw, Bb, C, D;

int main() {
  cin >> Aw >> Ab >> Bw >> Bb >> C >> D;
  if (Ab < C) Aw -= C - Ab, Bw += C - Ab;
  Aw += min(Bw, D);
  cout << Aw << endl;
  return 0;
}