#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;
}