#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 n,A[10000+1],q,key,sum=0;
    int i;
    
    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;
}