#include <iostream>
#include <algorithm>
using namespace std;
typedef long long LL;

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