#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, k;
  cin >> n >> m >> k;
  int power[n + 1];
  for (int i = 1; i <= n; i++) {
    cin >> power[i];
  }
  int school[n + 1];
  for (int i = 1; i <= n; i++) {
    cin >> school[i];
  }
  int choose[k + 1];
  for (int i = 1; i <= k; i++) {
    cin >> choose[i];
  }
  int count = 0;
  for (int i = 1; i <= k; i++) {
    for (int j = 1; j <= n; j++) {
      if (j == choose[i]) {
        int school_no = school[j];
        int curr_power = power[j];
        for (int k = 1; k <= n; k++) {
          if (school[k] == school_no && power[k] > curr_power) {
            count++;
            break;
          }
        }
        break;
      }
    }
  }
  cout << count << endl;
  return 0;
}
