#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>

using namespace __gnu_pbds;
using namespace std;

// using long doubles saves you from corner cases but is very time consuming
#define double      	long double
#define int         	long long
#define pb          	push_back
#define pii         	pair<int,int>
#define vi          	vector<int>
#define vii         	vector<pii>
#define mi          	map<int,int>
#define mii         	map<pii,int>
#define all(a)      	(a).begin(),(a).end()
#define sz(x)       	(int)x.size()
// just comment the line below in case of interactive problems
#define endl        	"\n"
#define repp(i,a,b) 	for(int i=a;i<b;i++)
#define rep(i,a,b) 		for(int i=a;i<=b;i++)
#define brep(i,a,b)     for(int i=a;i>=b;i--)
#define deb1(x)      	cout << #x << "=" << x << endl
#define deb2(x, y)  	cout << #x << "=" << x << "," << #y << "=" << y << endl
#define deb3(x, y, z)  	cout << #x << "=" << x << "," << #y << "=" << y << "," << #z << "=" << z << endl
#define trace(v) 		cout << #v << "=";for(auto it=v.begin();it!=v.end();it++)cout<<*it<<" ";cout<<endl;
#define tracearr(a,l,r) for(int iii=l;iii<=r;iii++)cout << a[iii] << " ";cout << endl;
#define PI          	3.1415926535897932384626
#define F 				first
#define S 				second
#define clr(x,y) 		memset(x, y, sizeof(x))
#define IOS         	ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
//vector<vector<int> > v( n , vector<int> (m, 0));


typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
// *s.find_by_order(1) - gives the 2nd samllest element in set
// s.order_of_key(x)   - gives the number of elements in the set which are strictly smaller than x


const int N=5000 + 5;
const int MOD=1e9 + 7;

int dp[N][N];

int n,m,x,y,a,b,c,d;

/*
	Fails here -
	484 401 678 439 991 638 823 706

	Expected o/p - 413977
	My o/p - 447789
*/

int solve(int cura,int curb){
    if(cura>=a && curb>=b){
        return 0;
    }
    int& ans = dp[cura][curb];
    if(ans!=-1)
        return ans;
    ans = 1e18;
    if(cura<2002){
        ans = min(ans,x + solve(cura+1,curb));
    }
    if(curb<2002){
        ans = min(ans,y + solve(cura,curb+1));
    }
    if(cura>=c && curb<b){
        ans = min(ans,solve(cura-c,curb+d));
    }
    if(curb>=d && cura<a){
        ans = min(ans,solve(cura+c,curb-d));
    }
    //deb3(cura,curb,ans);
    return ans;
}

void test_case()
{
    cin >> n >> m >> x >> y >> a >> b >> c >> d;
    clr(dp,-1);
    cout << solve(n,m) << endl;

}

int32_t main()
{
	/*#ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    #endif*/
	IOS;
	int T=1;
	//cin >> T;
	// int numOfSetBits = __builtin_popcountll(n);
	std::cout << std::fixed << std::setprecision(12);
	while(T--)
	{
		test_case();
	}
}

/*
	* while writing bool comp function for sorting put 1 statement in the end which has no if comdition
 	* in case of multiple test cases and N=1e5 don't intialize arrays as global except for graph vector-array
 	* always check whether or not you are doing mod of a negative number
 	* always use 1LL instead of 1
*/