#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, n, m, k;
  cin >> n >> m >> k;
  vector<int> pow(n + 1), sch(n + 1), hi(m + 1, 0);
  for (int i = 1; i <= n; i++) cin >> pow[i];
  for (int i = 1; i <= n; i++) {
    cin >> sch[i];
    if (pow[i] > hi[sch[i]]) hi[sch[i]] = pow[i];
  }
  int cnt = 0;
  for (int i = 1; i <= k; i++) {
    cin >> x;
    if (hi[sch[x]] > pow[x]) cnt++;
  }
  cout << cnt << endl;
  return 0;
}
