#include<stdio.h>

#define N 10000

int search(int *,int,int);


int main(){
  
  int i;
  int n, n2;
  int A[N], key;
  int count = 0;
  
  scanf("%d", &n);
  
  for ( i = 0 ; i < n ; i++ ) {
    scanf("%d", &A[i]);
  }

  
  scanf("%d", &n2);
  
  for ( i = 0 ; i < n2 ; i++ ){
    scanf("%d", &key);
    if ( search(A, n, key) ){
      count++;
    }
  }
  
  printf("%d\n", count);


  return 0;
}



int search(int A[], int n, int key){
  
  int i;
  
  for ( i = 0; i < n; i++ ){
    
    if ( A[i] == key ) {
      return 1;
    }
    
  }
  return 0;
}