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