#include <bits/stdc++.h>
using namespace std;
int const maxn = 1e5 + 5;
int n, m, k, p[105], second[105], mx[105];
int ans;
int main() {
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 1; i <= n; ++i) scanf("%d", &p[i]);
  for (int i = 1; i <= n; ++i) {
    scanf("%d", &second[i]);
    if (mx[second[i]] < p[i]) mx[second[i]] = p[i];
  }
  for (int i = 1; i <= k; ++i) {
    int v;
    scanf("%d", &v);
    if (mx[second[v]] > p[v]) ans++;
  }
  printf("%d\n", ans);
  return 0;
}
