#include <stdio.h>

#include <stdlib.h>

#define N 50

#define T 100005

typedef long long ll;

struct food {

int a, b, c;

}f[N];

int compare(const void *x, const void *y) {

return ((ll)((struct food *)x)->c * (ll)((struct food *)y)->b

< (ll)((struct food *)y)->c * (ll)((struct food *)x)->b) ? -1 : 1;

}

ll dp[T];

static inline ll max(ll a, ll b) { return a > b ? a : b; }

int main() {

int t, n, i, j;

scanf("%d %d", &t, &n);

for (i = 0; i < n; i++) scanf("%d", &f[i].a);

for (i = 0; i < n; i++) scanf("%d", &f[i].b);

for (i = 0; i < n; i++) scanf("%d", &f[i].c);

qsort(f, n, sizeof(f[0]), compare);

for (i = 0; i < n; i++)

for (j = t; j >= f[i].c; j--)

dp[j] = max(dp[j], dp[j - f[i].c] + f[i].a - j * (ll)f[i].b);

ll ans = 0ll;

for (i = 0; i <= t; i++)

ans = max(ans, dp[i]);

printf("%lld", ans);

exit(0);

}