#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;
}
