#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[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;
}
