#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;
}