#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,s[10000+1],q,key;
    int i,ans=0;
    
    scanf("%d",&n);
    for(i=0;i<n;i++) scanf("%d",&s[i]);
    scanf("%d",&q);
    for(i=0;i<q;i++){
	scanf("%d",&key);
	if(search(s,n,key)) ans++;
    }
    printf("%d\n",ans);
    return 0;
}