#include<iostream>
#include<string>
#include<string.h>
#include<algorithm>
#include<stdio.h>
#include<cmath>
#include<vector>
#include<utility>
#include<stack>
#include<queue>
#include<list>
#include<bitset>
#include<functional>

#define FOR(i, a, b) for(int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000

using namespace std;
typedef pair<int, int> P;

int main(void) {
	long long int aw, ab, bw, bb, c, d;

	cin >> aw >> ab >> bw >> bb >> c >> d;

	if (c - ab > 0) {
		aw -= (c - ab);
		bw += (c - ab);
	}
	if (d > bw) {
		aw += bw;
	}
	else {
		aw += d;
	}
	cout << aw << endl;
	return 0;
}