#include <stdio.h>

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

int main(){
  int i, n ,A[10000+1], q, key, sum=0;

  scanf("%d", &n);
  for(i=0; i<n; i++)
    scanf("%d", &A[i]);

  scanf("%d", &q);
  for(i=0; i<q; i++)
    {
      scanf("%d", &key);      
      if(search(A, n, key))
	sum++;
    }
  printf("%d\n", sum);
  
  return 0;
}

