#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[10001], 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;
}

