#include <bits/stdc++.h>
#include <iostream>
using namespace std;
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define rep(i,a,b) for(LL i = a;i<b; i++)
#define rrep(i,a,b) for(LL i = a;i>b; i--)
#define tobirep(i,a,b,c) for(LL i = a;i<b; i+=c)
#define tobirrep(i,a,b,c) for(LL i = a;i>b; i-=c)
#define INF ((1LL<<62)-(1LL<<31))
#define ooki 9223372036854775807
#define tii -9223372036854775808
typedef long long LL;
int main(){
   ios::sync_with_stdio(0);cin.tie(nullptr);
  LL aw,ab,bw,bb,c,d;
  cin >> aw >> ab >> bw >> bb >> c >> d;
  if(c>ab){aw-=c-ab;bw+=c-ab;ab=0;bb+=ab;}
  else { ab-=c;bb+=c;}
  if(d<=bw){ aw+=d;}
  else {aw+=bw;}
  cout << aw << endl;
 
}