#include <bits/stdc++.h>
using namespace std;
const double eps = 1e-6;
const double PI = acos(-1.0);
const int maxn = 105;
const int inf = 0x3f3f3f3f;
int n, m, k, c, ans, p[maxn], s[maxn], maxp[maxn];
int main() {
  while (cin >> n >> m >> k) {
    memset(maxp, 0, sizeof(maxp));
    ans = 0;
    for (int i = 1; i <= n; ++i) cin >> p[i];
    for (int i = 1; i <= n; ++i) {
      cin >> s[i];
      maxp[s[i]] = max(p[i], maxp[s[i]]);
    }
    for (int i = 1; i <= k; ++i) {
      cin >> c;
      if (p[c] != maxp[s[c]]) ans++;
    }
    cout << ans << endl;
  }
  return 0;
}
