#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;
}

