#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[10000+1],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;
}