#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(void){
  int i,n,A[10000],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;
}