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

const int kMAX_N = 16;
const int kMAX_T = 10010;

int N, T;
int c[kMAX_N], v[kMAX_N];

int max_value[kMAX_N][kMAX_T];

void Solve() {
    memset(max_value, -1, sizeof(max_value));
    max_value[0][0] = 0;

    for (int i = 0; i < N; i++) {
        for (int ti = 0; ti <= T; ti++) {
            if (max_value[i][ti] < 0) continue;

            int val = 0, next = v[i], times = 0;
            while (ti + c[i] * times <= T) {
                max_value[i + 1][ti + c[i] * times] = max(max_value[i + 1][ti + c[i] * times],
                                                          max_value[i][ti] + val);

                if (next == 0) break;
                val += next;
                times++;
                next /= 2;
            }
        }
    }

    int answer = 0;
    for (int ti = 0; ti <= T; ti++) answer = max(answer, max_value[N][ti]);
    cout << answer << endl;
}

int main() {
    cin >> T >> N;

    for (int i = 0; i < N; i++) {
        cin >> c[i];
    }

    for (int i = 0; i < N; i++) {
        cin >> v[i];
    }

    Solve();

    return 0;
}