#include<stdio.h>
#define N 10000
#define Q 500

int linearSearch();

int S[N],n,key;

int main(){
  int T[Q],q,i,c=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++){
    key=T[i];
    if(linearSearch()) c++;
  }

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

  return 0;
  
}

int linearSearch(){
  int i=0;

  S[n]=key;

  while(S[i]!=key) i++;

  if(i==n) return 0;

  return 1;
}