#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
void solve() {
  long long n, m, k;
  cin >> n >> m >> k;
  std::vector<long long> power(n);
  std::vector<long long> school(n);
  std::vector<long long> mx(m + 1);
  std::vector<long long> stud(n);
  for (long long i = 0; i < n; i++) {
    cin >> power[i];
  }
  for (long long i = 0; i < n; i++) {
    cin >> school[i];
  }
  for (long long i = 0; i < k; i++) {
    cin >> stud[i];
  }
  for (long long i = 0; i < n; i++) {
    mx[school[i]] = max(power[i], mx[school[i]]);
  }
  long long count = 0;
  for (long long i = 0; i < k; i++) {
    if (mx[school[stud[i] - 1]] > power[stud[i] - 1]) {
      count++;
    }
  }
  cout << count << "\n";
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long t = 1;
  for (long long i = 1; i <= t; i++) {
    solve();
  }
  return 0;
}
