#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
using namespace std;

int main()
{
    int w1, b1, w2, b2, c, d;
    cin >> w1 >> b1 >> w2 >> b2 >> c >> d;

    int x = max(0, c - b1);
    int ret = w1 - x + min(d, w2 + x);
    cout << ret << endl;

    return 0;
}