#include <iostream>
#define FOR(i,a,b) for(int i=a; i<b; i++)
#define REP(i,n) FOR(i,0,n)

int main(){
  int i, aw, ab, bw, bb, c, d;

  std::cin >> aw >> ab >> bw >> bb >> c >> d;

  REP(i, c){
    if(ab > 0){
      ab -= 1;
      bb += 1;
    }
    else{
      aw -= 1;
      bw += 1;
    }
  }
  REP(i, d){
    if(bw > 0){
      bw -= 1;
      aw += 1;
    }
  }

  std::cout << aw << std::endl;
}