#include<stdio.h>

//線形探索

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;
}
	
