#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;
}