#include <bits/stdc++.h>
using namespace std;
int N, M, K, ans;
int power[105], school[105];
int main() {
  scanf("%d %d %d", &N, &M, &K);
  for (int i = 1; i <= N; i++) scanf("%d", &power[i]);
  for (int i = 1; i <= N; i++) scanf("%d", &school[i]);
  for (int i = 0, a; i < K; i++) {
    scanf("%d", &a);
    int p = power[a], s = school[a];
    for (int i = 1; i <= N; i++) {
      if (school[i] == s) {
        if (power[i] > p) {
          ans++;
          break;
        }
      }
    }
  }
  printf("%d\n", ans);
  return 0;
}
