#include <bits/stdc++.h>
using namespace std;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int aw, ab, bw, bb, c, d;
	cin >> aw >> ab >> bw >> bb >> c >> d;
	int ans = aw - (c - ab);
	bw += c - ab;
	ans += min(bw, d);
	cout << ans << endl;
	return 0;	
}