//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define all(a) (a).begin(), (a).end()
using ll = long long;
const ll INF32 = 2e9;
const ll INF64 = 4e18;

void printYN(bool ok){
    if(ok)cout << "Yes" << endl;
    else cout << "No" << endl;
    return;
}

bool check(ll mid,ll R, ll P, ll Q, ll A, ll B, ll C, ll D){
    R -= mid*P;    
    ll E = max(0LL, A-mid)+max(0LL, B-mid)+max(0LL, C-mid);
    ll F = max(0LL, mid-A)+max(0LL, mid-B)+max(0LL, mid-C);
    if(D+E<F)return false;
    R-=F*Q;
    return R>=0;
}

int main() {
    ll R, P, Q;
    cin >> R >> P >> Q;
    ll A, B, C, D;
    cin >> A >> B >> C >> D;
    ll ok = 0, ng = 1e10;
    while(ng-ok>1){
        ll mid = (ok+ng)/2;
        if(check(mid, R,P, Q, A, B, C, D))ok = mid;
        else ng = mid;    
    }
    cout << ok << endl;
    return 0;
}