#include <bits/stdc++.h>
using namespace std;
const int N = 2005, M = 4005;
const int INF = (int)1e9;
int n, m;
int l[N], s[N];
int c[M];
int dp[M][M];
void umax(int& to, int val) { to = max(to, val); }
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  cin >> n >> m;
  for (int i = 0; i < n; i++) cin >> l[i];
  for (int i = 0; i < n; i++) cin >> s[i];
  for (int i = 1; i <= n + m; i++) cin >> c[i];
  for (int i = 0; i < M; i++) {
    fill(dp[i], dp[i] + M, -INF);
    dp[i][0] = 0;
  }
  for (int i = n - 1; i >= 0; i--) {
    for (int j = M - 1; j >= 1; j--) {
      if (dp[l[i]][j - 1] != -INF)
        umax(dp[l[i]][j], dp[l[i]][j - 1] + c[l[i]] - s[i]);
    }
    int up = M - 1;
    for (int a = l[i]; a <= m + n - 1; a++) {
      for (int j = 0; j <= up; j++) {
        if (dp[a][j] != -INF)
          umax(dp[a + 1][j / 2], dp[a][j] + (j / 2) * c[a + 1]);
      }
      up = up / 2;
    }
  }
  int res = -INF;
  for (int i = 0; i <= n + m; i++)
    for (int j = 0; j <= 1; j++) {
      res = max(res, dp[i][j]);
    }
  cout << res << '\n';
}
