#include <bits/stdc++.h>
using namespace std;
int p[105], c[105];
int mm[105];
int n, m, k, t, ans;
int main() {
  cin >> n >> m >> k;
  for (int i = 1; i <= n; i++) {
    cin >> p[i];
  }
  for (int i = 1; i <= n; i++) {
    cin >> c[i];
    mm[c[i]] = max(mm[c[i]], p[i]);
  }
  for (int i = 1; i <= k; i++) {
    cin >> t;
    if (p[t] != mm[c[t]]) ans++;
  }
  cout << ans;
}
