#include <iostream>
using namespace std;
typedef long long ll;

int main(){
    ll H, W, LA, LB, KA, KB;
    cin >> H >> W >> LA >> LB >> KA >> KB;

    ll ans = H + W + 1;

    for (ll i = 0; i <= H; i++){
        for (ll j = 0; j <= W; j++){
            ll tate = min(H, LA * i);
            ll yoko = min(W, LB * j);
            ll ka_sum = KA * i;
            ll kb_sum = KB * j;
            if (ka_sum + kb_sum >= H * W - tate * yoko){
                ans = min(ans, i + j);
            }
        }
    }
    cout << ans << endl;
}