//p1909
#include<bits/stdc++.h>
using namespace std;
int n;
int a,b,c,d,e,f;
int main(){
	cin>>n;
	cin>>a>>b>>c>>d>>e>>f;
	int a1=n%a==0?n/a*b:(n/a+1)*b;
	int b1=n%c==0?n/c*d:(n/c+1)*d;
	int c1=n/e==0?n/e*f:(n/e+1)*f;
	cout<<min(a1,min(b1,c1));
}