#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(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;
}
