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

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define pb push_back
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

int main() {
	cin.tie(0)->sync_with_stdio(0);
    vector<int> need(3), have(3);
    for(int i = 0; i < 3; i++)
        cin >> need[i];
    for(int i = 0; i < 3; i++)
        cin >> have[i];
    int red = max(0, need[0]-have[0]);
    int green = max(0, need[1]-have[1]);
    int blue = max(0, need[2]-have[2]);
    int rg, gb;
    cin >> rg >> gb;
    int ans = 1000000;
    bool found = false;
    for(int i = 0; i <= rg; i++) {
        for(int j = 0; j <= gb; j++) {
            int RG = i;
            int GB = j;
            RG -= red;
            GB -= blue;
            if(RG >= 0 && GB >= 0 && RG+GB >= green) {
                ans = min(ans, i+j);
                found = true;
            }
        }
    }
    if(!found)
        ans = -1;
    cout << ans << "\n";
}