#include<iostream>
#include<cmath>
using namespace std;

int main(){
	int n;
	int p_count[3];
	int p_price[3];
	int min_price;
	long long price[3];
	
	min_price = price[0];
	
	scanf("%d",&n);
	
	for(int i=0;i<3;i++){
		scanf("%d%d",&p_count[i],&p_price[i]);
		price[i]=p_price[i] * ceil(1.0*n/p_count[i]);	
		if(price[i]<min_price)
			min_price = price[i];
	}

	
	printf("%d",min_price);
	
	return 0;
}