#include<bits/stdc++.h>
using namespace std;
int main()
{
	long long int n,x1,x2,x3,x4,x5,x6,a,b,c;
	scanf("%d",&n);
	scanf("%d %d",&x1,&x2);
	scanf("%d %d",&x3,&x4);
	scanf("%d %d",&x5,&x6);
	if(n%x1==0)
		{a=n/x1*x2;}
	else
		{a=(n/x1+1)*x2;}
	if(n%x3==0)
		{b=n/x3*x4;}
	else
		{b=(n/x3+1)*x4;}
	if(n%x5==0)
		{c=n/x5*x6;}
	else
		{c=(n/x5+1)*x6;}
	
	if(a>b)
		swap(a,b);
	if(a>c)
		swap(a,c);
	printf("%d",&a);
	return 0;
}