#include<stdio.h>
int linearSearch(int A[], int n, int key){
  int i = 0;

  A[n] = key;
  while(A[i] != key)
    i++;
  if(i == n)   return 0;
  else         return 1;
}

int main(){
  int n, S[10000], q, T[10000], i, cnt = 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", &T[i]);
   
  for(i = 0; i < n; i++)
    if(linearSearch(S, n, T[i]) == 1 && i < q)
      cnt++;

  printf("%d\n", cnt);
  return 0;
}