#include <stdio.h>
#define INF 100000000
 
int min(int a, int b) {
    return a < b ? a : b;
}
 
int main() {
    int n;
    int s, sn;  // s: 値段, sn: 卵の数
    int m, mn;
    int l, ln;
 
    scanf("%d", &n);
    scanf("%d %d", &sn, &s);  // Sパック：sn個入り, s円
    scanf("%d %d", &mn, &m);  // Mパック：mn個入り, m円
    scanf("%d %d", &ln, &l);  // Lパック：ln個入り, l円
 
    int sum = INF;
 
    // 最大でもnより少し多くなるまで探索すれば十分
    for (int i = 0; i <= n / sn + 10; i++) {
        for (int j = 0; j <= n / mn + 10; j++) {
            for (int k = 0; k <= n / ln + 10; k++) {
                int total_eggs = i * sn + j * mn + k * ln;
                if (total_eggs >= n) {
                    int cost = i * s + j * m + k * l;
                    sum = min(sum, cost);
                }
            }
        }
    }
 
    printf("%d", sum);
    return 0;
}

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OAo0IDEwMAoxMCAxOTAKMTIgMjAw

8
4 100
10 190
12 200