#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;
	
}

