#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m = 0, k, ans = 0, sc;
  cin >> n >> m >> k;
  vector<int> school[101];
  int p[n + 1], s[n + 1], c[k];
  for (int i = 1; i <= n; i++) cin >> p[i];
  for (int i = 1; i <= n; i++) {
    cin >> s[i];
    school[s[i]].push_back(p[i]);
  }
  for (int i = 0; i < k; i++) cin >> c[i];
  for (int i = 0; i < k; i++) {
    int temp = c[i];
    int ma = *(max_element(school[s[temp]].begin(), school[s[temp]].end()));
    if (p[temp] < ma) {
      ans++;
    }
  }
  cout << ans;
}
