#include<stdio.h>

int S(int T[],int n, int key);


int main(){
  int i,n,T[10000+1],q,key,sum =0;

  scanf("%d",&n);
  for(i=0;i<n;i++) scanf("%d",&T[i]);

  scanf("%d",&q);
  for(i=0;i<q;i++){
    scanf("%d",&key);
    if(S(T,n,key))sum++;
  }
  printf("%d\n",sum);

  return 0;
}


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

