#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, k, cnt = 0;
  scanf("%d %d %d", &n, &m, &k);
  int p[n], s[n], c[k];
  for (int i = 0; i < n; i++) scanf("%d", &p[i]);
  for (int i = 0; i < n; i++) scanf("%d", &s[i]);
  for (int i = 0; i < k; i++) scanf("%d", &c[i]);
  for (int i = 0; i < k; i++) {
    int po = p[c[i] - 1];
    int so = s[c[i] - 1];
    for (int j = 0; j < n; j++) {
      if (p[j] > po && s[j] == so) {
        cnt++;
        break;
      }
    }
  }
  printf("%d\n", cnt);
  return 0;
}
