#include<stdio.h>

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

int main(){
  int i,n,A[10001],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(linearSearch(A,n,key))sum++;
  }
  printf("%d\n",sum);
  
  return 0;
}

