#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(void){
	int i,n,A[100000],q,key;
	int cnt=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)){cnt++;}
	}
	
	printf("%d\n",cnt);
	
	return 0;
}
