/* -*- coding: utf-8 -*-
 *
 * 37.cc: No.37 遊園地のアトラクション - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 15;
const int MAX_T = 10000;

const int INF = 1 << 30;

/* typedef */

/* global variables */

int cs[MAX_N], vs[MAX_N], dp[2][MAX_T + 1];

/* subroutines */

int n_knapsak(int n, int m, int *cs, int *vs) {
  memset(dp, -1, sizeof(dp));
  dp[0][0] = 0;
  int cur = 0, nxt = 1;

  for (int i = 0; i < n; i++) {
    memcpy(dp[nxt], dp[cur], sizeof(dp[cur]));

    int ci = cs[i], c = ci;
    int vi = vs[i], v = vi;

    while (c <= m) {
      int max_j = m - c;
      for (int j = 0; j <= max_j; j++)
        if (dp[cur][j] >= 0) {
          int d = dp[cur][j] + v;
          if (dp[nxt][j + c] < d) dp[nxt][j + c] = d;
        }
      c += ci;
      vi /= 2;
      v += vi;
    }

    cur ^= 1; nxt ^= 1;
  }

  int max_d = 0;
  for (int i = 0; i <= m; i++)
    if (max_d < dp[cur][i]) max_d = dp[cur][i];
  
  return max_d;
}

/* main */

int main() {
  int t, n;
  cin >> t >> n;

  for (int i = 0; i < n; i++) cin >> cs[i];
  for (int i = 0; i < n; i++) cin >> vs[i];

  int maxd = n_knapsak(n, t, cs, vs);
  printf("%d\n", maxd);
  return 0;
}