#include <bits/stdc++.h>
using namespace std;
const int inf = 0x3f3f3f3f;
const long long INF = 0x3f3f3f3f3f3f3f3fLL;
const double PI = acos(-1.0);
const long double eps = 1e-6;
const int mod = 1e9 + 7;
const int maxn = 2e5 + 50;
const int M = 3e6 + 10;
const int N = 1e5 + 10;
int p[105], s[105], mx[105];
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m, k;
  cin >> n >> m >> k;
  for (int i = 1; i <= n; ++i) cin >> p[i];
  for (int i = 1; i <= n; ++i) {
    cin >> s[i];
    mx[s[i]] = max(p[i], mx[s[i]]);
  }
  int a, sum = 0;
  for (int i = 0; i < k; ++i) {
    cin >> a;
    if (p[a] != mx[s[a]]) ++sum;
  }
  cout << sum << endl;
  return 0;
}
