#include <bits/stdc++.h>
using namespace std;
using namespace std::chrono;
const int N = 1e6, M = N, inf = (int)1e9;
const long long mod = 1e9 + 7;
int fastAbs(int n) { return (n ^ (n >> 31)) - (n >> 31); }
long long multiply(long long a, long long b) {
  return ((a % mod) * (b % mod)) % mod;
}
long long add(long long a, long long b) {
  return ((a % mod) + (b % mod)) % mod;
}
long long sub(long long a, long long b) {
  return ((a % mod) - (b % mod) + mod) % mod;
}
int ans;
map<pair<int, int>, int> mp;
const int dx[4] = {1, 0, 0, -1};
const int dy[4] = {0, -1, 1, 0};
bool inside(int r, int c, int n) {
  return ((r >= 0 && r < n) && (c >= 0 && c < n));
}
int binarySearch(vector<int> arr, int l, int r, int x) {
  if (r >= l) {
    int mid = l + (r - l) / 2;
    if (arr[mid] == x) return mid;
    if (arr[mid] > x) return binarySearch(arr, l, mid - 1, x);
    return binarySearch(arr, mid + 1, r, x);
  }
  return -1;
}
void solve() {
  int n, m, k;
  cin >> n >> m >> k;
  vector<int> p(n), s(n);
  for (int i = 0; i < n; i++) cin >> p[i];
  for (int i = 0; i < n; i++) cin >> s[i];
  vector<int> c(k);
  int ans = 0;
  for (int i = 0; i < k; i++) cin >> c[i];
  for (int i = 0; i < k; i++) {
    int id = c[i] - 1;
    int school = s[id];
    for (int j = 0; j < n; j++) {
      if (s[j] == school && p[id] < p[j]) {
        m++;
        s[id] = m;
        ans++;
        break;
      }
    }
  }
  cout << ans;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int q = 1;
  while (q--) solve();
}
