#include <bits/stdc++.h>
using namespace std;
void solve() {
  int n, m, k;
  cin >> n >> m >> k;
  vector<int> a(n + 1), b(n + 1);
  for (int i = 1; i < n + 1; ++i) {
    cin >> a[i];
  }
  for (int i = 1; i < n + 1; ++i) {
    cin >> b[i];
  }
  int ret = 0;
  for (int i = 1; i < k + 1; ++i) {
    int x;
    cin >> x;
    for (int j = 1; j < n + 1; ++j) {
      if (b[j] == b[x] && a[j] > a[x]) {
        ++ret;
        break;
      }
    }
  }
  cout << (ret) << '\n';
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  solve();
  return 0;
}
