#include <iostream>
#include <cmath> 
#include <iomanip>
using namespace std;
int main()
{
	int n,c1,c2,c3,p1,p2,p3,pp,min;
	cin>>n>>c1>>c2>>c3>>p1>>p2>>p3>>pp>>min;
	if(n%c1==0)
	{
		pp=n/c1*p1;
	}
	else
	{
		pp=(n/c1+1)*p1;
	}
	min=pp;
	if(n/c2*p1)
	{
		pp=n/c2*p2;
	}
	else
	{
		pp=(n/c2+1)*p2;
	}
	if(min>pp)
	{
		min=pp;
	}
	if(n%c3==0)
	{
		pp=n/c3*p3;
	}
	else
	{
		pp=(n/c3+1)*p3;
	}
	if(min>pp)
	{
		min=pp;
	}
	cout<<min<<endl;
	return 0;
}