#include<iostream>
#include<string>
#include<algorithm>
#include<cmath>
#include<iomanip>
#include<cstring>
#include<map>
#include<vector>
using namespace std;
typedef long long int ll;

int main(){

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