import java.util.*;
import static java.lang.Math.*;

public class Main {
    private void solve() {
        Scanner sc = new Scanner(System.in);
        int aw = sc.nextInt();
        int ab = sc.nextInt();
        int bw = sc.nextInt();
        int bb = sc.nextInt();
        int c = sc.nextInt();
        int d = sc.nextInt();
        int lagmark = min(ab, c);
        aw -= c - lagmark;
        bw += c - lagmark;
        System.out.println(aw + min(bw, d));
    }

    public static void main(String[] args) {
        new Main().solve();
    }
}