#include<stdio.h>


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


int main(){
  int i,A[10000+1],n,q,k,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",&k);
    if(search(A,n,k)) sum++;
  }

  printf("%d\n",sum);

  return 0;
}



