#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n, m, k;
  cin >> n >> m >> k;
  int p[105];
  int s[105];
  priority_queue<int> pq[105];
  for (int i = 0; i < n; i++) cin >> p[i];
  for (int i = 0; i < n; i++) {
    cin >> s[i];
    pq[s[i]].push(p[i]);
  }
  int count = 0;
  for (int i = 0; i < k; i++) {
    int j;
    cin >> j;
    int theschool = s[j - 1];
    int thepower = p[j - 1];
    if (pq[theschool].top() > thepower) count++;
  }
  cout << count << endl;
  return 0;
}
