#include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define codefor int test;cin>>test;while(test--)
#define INT(...) int __VA_ARGS__;in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;in(__VA_ARGS__)
#define vector2d(type,name,h,...) vector<vector<type>>name(h,vector<type>(__VA_ARGS__))
#define vector3d(type,name,h,w,...) vector<vector<vector<type>>>name(h,vector<vector<type>>(w,vector<type>(__VA_ARGS__)))
using namespace std;
template<class T> using rpriority_queue = priority_queue<T, vector<T>, greater<T>>;
template<class T> istream& operator>>(istream& is, vector<T>& vec) {for(T& x : vec)is >> x;return is;}
template<class T> ostream& operator<<(ostream& os, const vector<T>& vec) {if(vec.empty())return os;os << vec[0];for(auto it = vec.begin(); ++it!= vec.end();)os << ' ' << *it;return os;}
void in(){}
template <class Head, class... Tail> void in(Head& head, Tail&... tail){cin >> head;in(tail...);}
void out(){cout << '\n';}
template<class T>void out(const T& a){cout << a << '\n';}
template <class Head, class... Tail> void out(const Head& head,const Tail&... tail){cout << head << ' ';out(tail...);}
const int INF = 1 << 30;
const long long INF2 = 1ll << 60;
template<class T> void chmax(T &a,const T b){if(b>a)a=b;}
template<class T> void chmin(T &a,const T b){if(b<a)a=b;}


using ll = long long;

template<typename T>
T MUL(T a, T b){
    T res;
    return __builtin_mul_overflow(a, b, &res)? std::numeric_limits<T>::max() : res;
}

int main(){
    //clock_t finish = clock() + CLOCKS_PER_SEC / 1000 * 1960;
    ios::sync_with_stdio(false);
    cin.tie(0);
    LL(h, w, la, lb, ka, kb);
    ll v = h * w, S = la * lb, ans = 1ll << 60;
    for(ll i = 0; i <= 2000000; i++){
        ll rem = v - ka * i;
        ll ng = -1, ok = v, mid;
        if(kb >= 1) ok = v / kb + 1;
        while(ng + 1 < ok){
            mid = (ok + ng) / 2;
            if(min(h, MUL(la, i)) * min(w, MUL(lb, mid)) + kb * mid >= rem) ok = mid;
            else ng = mid;
        }
        chmin(ans, i + ok);
    }
    for(ll i = 0; i <= 2000000; i++){
        ll rem = v - kb * i;
        ll ng = -1, ok = v, mid;
        if(ka >= 1) ok = v / ka + 1;
        while(ng + 1 < ok){
            mid = (ok + ng) / 2;
            if(min(h, MUL(la, mid)) * min(w, MUL(lb, i)) + ka * mid >= rem) ok = mid;
            else ng = mid;
        }
        chmin(ans, i + ok);
    }
    out(ans);
}