#include<iostream>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
int n,money=99999,a,b,temp; 
int main()
{
	cin>>n;
	for(int i=1; i<=3; i++)
	{
		cin>>a>>b;
		if(n%a!=0)
		{
			temp=n/a+1;
		}
		else
		{
			temp=n/a;
		}
		temp*=b;
		money=min(money,temp);
	}
	cout<<money;
	return 0;
}