import java.util.*;

public class Run {
    final static int M = 1000000007;
    public static void main (String arg[]) {
        Scanner scan = new Scanner(System.in);
        int Aw,Ab,Bw,Bb,C,D;
        Aw = scan.nextInt();
        Ab = scan.nextInt();
        Bw = scan.nextInt();
        Bb = scan.nextInt();
        C = scan.nextInt();
        D = scan.nextInt();
        int r;
        if (Ab < C) {
            r = C - Ab;
            Aw -= r;
            Bw += r;
            if (Bw > D) Aw += D;
            else Aw += Bw;
        } else {
            if (Bw > D) Aw += D;
            else Aw += Bw;
        }
        System.out.println(Aw);
    }
}