#include<stdio.h>

#define N1 10000
#define N2 500

int main(){
  int S[N1+1];
  int T[N2+1];
  int n,q,i,j;
  int count=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<=q;i++){
    for(j=0;j<=n;j++){
      if(S[i]==T[j]){
	count++;
	break;
      }	
    }
  }
  
  printf("%d\n",count);
  return 0;
}