import java.util.Scanner;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;

class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int aw = in.nextInt();
        int ab = in.nextInt();
        int bw = in.nextInt();
        int bb = in.nextInt();
        int c = in.nextInt();
        int d = in.nextInt();

        if(c > ab) {
            aw = aw - (c - ab);
            bw = bw + (c - ab);
        }

        if(d > bw) {
            aw = aw + bw;
        } else {
            aw = aw + d;
        }

        System.out.println(aw);

        in.close();
    }
}