#include<stdio.h>

int LinearSearch(int [],int,int);

int main(){
  int i,n,A[10001],j,key,sum = 0;

  scanf("%d",&n);
  for(i = 0;i< n;i++){
    scanf("%d",&A[i]);
  }
  scanf("%d",&j);
  for(i = 0;i < j;i++){
    scanf("%d",&key);
    if(LinearSearch(A,n,key))
      sum++;
  }
  printf("%d\n",sum);

  return 0;
}

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


