#include <bits/stdc++.h>
int kensaku(int S[], int T[], int Q, int N) {
  int i = 0, j = 0, k = 0, z = 0;
  int zcount = 0, EOFcount = 0, V[100000];
  for (j = 0; j < N; j++) {
    for (i = 0; i < Q; i++) {
      if (T[i] == S[j]) {
        for (k = 0; k < zcount; k++) {
          if (T[i] == V[k]) {
            EOFcount++;
          }
        }
        if (EOFcount == 0) {
          V[z] = T[i];
          z++;
          zcount++;
        }
        EOFcount = 0;
      }
    }
  }
  return zcount;
}
int main(void) {
  int i;
  int n, q, count = 0;
  int s[100000], t[100000];
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    scanf("%d", &s[i]);
  }
  scanf("%d", &q);
  for (i = 0; i < q; i++) {
    scanf("%d", &t[i]);
  }
  printf("%d\n", count = kensaku(s, t, q, n));
  return 0;
}
