#include <stdio.h>
 
int BinarySearch(int, int, int*);
 
 
main(){
 
  int n,q,i,s;
  int S[1000000];
  int count = 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",&s);
    if(BinarySearch(s,n,S) == 0){
      count++;
    }
  }
 
  printf("%d\n",count);
 
  return 0;
}
 
 
int BinarySearch(int key,int n,int S[]){
 
  int l=0,m,r;
 
  r = n;
 
  while(l < r){
    m = (r + l)/2;  
     
    if(S[m] == key)return 0;
     
    else if(S[m] > key)r = m;
 
    else l = m+1;
  }
 
  return 1;
}
