#include<stdio.h>
int main() {
	int n=0;
	int num[100];
	int price[100];
	int pay[10];
	scanf_s("%d", &n);
	for (int i = 1; i < 4; i++) {
		scanf_s("%d \t%d", &num[i], &price[i]);
	}
	for (int i = 1; i < 4; i++) {
		if (n % num[i] == 0) {
			pay[i] = price[i] * (n / num[i]);
		}
		else {
			pay[i] = price[i] * ((n / num[i]) + 1);
		}
	}
	int sum = pay[1];
	for (int i = 1; i < 4; i++) {
		if (pay[i] <= sum) {
			sum = pay[i];
		}
	}
	printf("%d",sum);
	return 0;

}