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++){
		scnf("%d", &key);
		if( search(A, n, key) ) sum++;
	}
	printf("%d\n", sum);
	
	return 0;
}