#include<bits/stdc++.h>
using namespace std;
#include<atcoder/all>
using namespace atcoder;
using ll = long long;
ll H,W,LA,LB,KA,KB;

ll bs(ll A){//Akai punch
	ll yoko = min(H,LA*A);
	ll Aboth = min(H*W,KA*A);
	ll ng = -1,ok = W+2;
	while(abs(ok-ng)>1){
		ll mid = (ok+ng)/2;
		ll tate = min(W,LB*mid);
		ll Bboth = min(H*W,KB*mid);
		if(tate*yoko+Aboth+Bboth>=H*W){
			ok = mid;
		}else{
			ng = mid;
		}
	}
	ll tate = min(W,LB*ok);
	ll Bboth = min(H*W,KB*ok);
	if(tate*yoko+Aboth+Bboth>=H*W){
	}else{
		ok = 1e9;
	}
	return ok;
}

void solve(){
	ll ans = 1e9;
	for(int i = 0;i<=H;i++){
		ans = min(ans,bs(i)+i);
	}
	cout<<ans<<endl;
}

signed main(){
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	cin >> H >> W>>LA>>LB>>KA>>KB;
	solve();
}