#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC optimize("O3", "unroll-loops")
#pragma GCC target("avx,avx2,fma")
long long int add(long long int x, long long int y) {
  long long int res = x + y;
  return (res >= 1000000007 ? res - 1000000007 : res);
}
long long int mul(long long int x, long long int y) {
  long long int res = x * y;
  return (res >= 1000000007 ? res % 1000000007 : res);
}
long long int sub(long long int x, long long int y) {
  long long int res = x - y;
  return (res < 0 ? res + 1000000007 : res);
}
long long int power(long long int x, long long int y) {
  long long int res = 1;
  x %= 1000000007;
  while (y) {
    if (y & 1) res = mul(res, x);
    y >>= 1;
    x = mul(x, x);
  }
  return res;
}
long long int mod_inv(long long int x) { return power(x, 1000000007 - 2); }
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  {
    int n, m, k;
    cin >> n >> m >> k;
    int a[n], b[n];
    map<int, int> op;
    for (int i = 0; i < n; i++) {
      cin >> a[i];
    }
    for (int i = 0; i < n; i++) {
      cin >> b[i];
      op[b[i]] = max(op[b[i]], a[i]);
    }
    int ans = 0;
    for (int i = 0; i < k; i++) {
      int x;
      cin >> x;
      if (op[b[x - 1]] != a[x - 1]) {
        ans++;
      }
    }
    cout << ans << "\n";
  }
  cerr << "time taken : " << (float)clock() / CLOCKS_PER_SEC << " secs"
       << "\n";
  return 0;
}
