#include <stdio.h>

// 線形探索
int search(int A[], int n, int key) {
	int i = 0;
	A[n] = key;
	while(A[i] != key) i++;
	return i != n;
}

int main(void) {
	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;
}