#include <bits/stdc++.h>
using namespace std;
int scAndMaxPow[105];
struct data {
  int power, sc;
};
int main() {
  int n, m, k, i, j, l, p, s;
  struct data ar[105];
  cin >> n >> m >> k;
  for (i = 1; i <= n; i++) {
    cin >> ar[i].power;
  }
  for (i = 1; i <= n; i++) {
    cin >> ar[i].sc;
  }
  for (i = 1; i <= n; i++) {
    scAndMaxPow[ar[i].sc] = max(scAndMaxPow[ar[i].sc], ar[i].power);
  }
  int cnt = 0;
  for (i = 1; i <= k; i++) {
    cin >> p;
    if (ar[p].power == scAndMaxPow[ar[p].sc]) cnt++;
  }
  cout << abs(k - cnt) << endl;
}
