// No.149 碁石の移動
// https://yukicoder.me/problems/no/149
//

#include <iostream>
using namespace std;


int main() {
    int Aw, Ab, Bw, Bb;
    int C, D;
    cin >> Aw >> Ab;
    cin >> Bw >> Bb;
    cin >> C >> D;

    // C個の移動
    if (C <= Ab) {
        Bb += C;
        Ab -= C;
    } else {
        Bb += Ab;
        Aw -= (C - Ab);
        Bw += (C - Ab);
        Ab = 0;
    }

    // D個の移動
    if (D <= Bw)
        Aw += D;
    else
        Aw += Bw;

    cout << Aw << endl;
}