#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<ll,ll>;
#define fix(x) fixed << setprecision(x)
#define asc(x) x, vector<x>, greater<x>
#define rep(i, n) for(ll i = 0; i < n; i++)
#define all(x) (x).begin(),(x).end()
template<class T>bool chmin(T&a, const T&b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool chmax(T&a, const T&b){if(a<b){a=b;return 1;}return 0;}
constexpr ll INFLL = (1LL << 62), MOD = 998244353;
constexpr int INF = (1 << 30);

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    ll h,w,la,lb,ka,kb;
    cin >> h >> w >> la >> lb >> ka >> kb;
    ll ans = INFLL;
    rep(houren,2){
        for(int i=0;i<=h/la+1;i++){
            ll remh = max((h - i*la)*w - ka*i, 0LL);
            ll remw = max(h*w - ka*i, 0LL);
            ll upd = (remw+lb*h+kb-1)/(lb*h+kb);
            if(kb){
                upd += (remh+kb-1)/kb;
            }else{
                if(remh) upd = INFLL;
            }
            chmin(ans, i+upd);
        }
        swap(h,w);
        swap(la,lb);
        swap(ka,kb);
    }
    cout << ans << '\n';
    return 0;
}