#include <bits/stdc++.h>
using namespace std;
namespace IO {
template <class T>
inline void read(T &x) {
  x = 0;
  int f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch <= '9' && ch >= '0') x = x * 10 + ch - '0', ch = getchar();
  x *= f;
}
};  // namespace IO
using namespace IO;
const int oo = 0x3f3f3f3f;
const int N = 5005;
int n, m, l[N], s[N], c[N << 1], dp[N][N], ans;
int main() {
  read(n), read(m);
  for (int i = (1); i <= (n); ++i) read(l[i]);
  for (int i = (1); i <= (n); ++i) read(s[i]);
  for (int i = (1); i <= (n + m); ++i) read(c[i]);
  memset(dp, -oo, sizeof(dp));
  for (int i = (1); i <= (n + m); ++i) dp[i][0] = 0;
  for (int i = (n); i >= (1); --i) {
    for (int j = (n + m - 1); j >= (0); --j)
      dp[l[i]][j + 1] = max(dp[l[i]][j + 1], dp[l[i]][j] + c[l[i]] - s[i]);
    int num = n - i + 1;
    for (int j = (l[i]); j <= (n + m - 1); ++j) {
      for (int k = (0); k <= (num); ++k)
        dp[j + 1][k / 2] = max(dp[j + 1][k / 2], dp[j][k] + (k / 2) * c[j + 1]);
      num /= 2;
    }
  }
  for (int i = (1); i <= (n + m); ++i) ans = max(ans, dp[i][1]);
  printf("%d\n", ans);
  return 0;
}
