#include<stdio.h>

int search(int A[],int n,int key){
	int = 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]);
	
	sanf("%d",&q);
	for(i=0; i<q; i++){
		scanf("%d", &key);
		if(search(A, n, key))sum++;
	}
	printf("%d\n", sum);
	
	return 0;
}
		