#include<stdio.h>

#define M 10000

int liner_search(int[], int, int);

int main(void) {
  int i, n, S[M+4], q, key, sum=0;

  scanf("%d", &n);
  for(i=0; i<n; i++) {
    scanf("%d", &S[i]);
  }
  scanf("%d", &q);
  for(i=0; i<q; i++) {
    scanf("%d", &key);
    if(liner_search(S, n, key)) sum++;
  }
  printf("%d\n", sum);

  return 0;
}

int liner_search(int S[], int n, int key) {
  int i=0;
  S[n]=key;
  while(S[i]!=key) i++;
  
  return i!=n;
}

