#include <stdio.h>
 
int search(int A[],int n,int key){
 
int i = 0;
A[n] = key;
while(A[i] != key)i++;
return i != n;
}
 
 
int main(){
int i,n,A[100000],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(search(A,n,key))sum++;
}
printf("%d\n",sum);
 
return 0;
}

