#include <bits/stdc++.h>
using namespace std;
int p[111], s[111], v[111];
int main() {
  int n, m, k, i, Nr = 0, c;
  cin >> n >> m >> k;
  for (i = 1; i <= n; ++i) cin >> p[i];
  for (i = 1; i <= n; ++i) {
    cin >> s[i];
    if (p[i] > v[s[i]]) v[s[i]] = p[i];
  }
  for (i = 1; i <= k; ++i) {
    cin >> c;
    if (p[c] < v[s[c]]) Nr++;
  }
  cout << Nr << "\n";
  return 0;
}
