#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", sum);

	return 0;
}