#include <iostream>
#include <algorithm>
using namespace std;
void main()
{
int v[15000],s,z=0,i,j,n,st,t;
cin>>n;
for (i = 0; i <=n-1; i++) cin>>v[i];
cin>>st;
for (i = 0; i <=st-1; i++)
{
cin>>s;
if(binary_search(v,v+n,s)==true)z++;
}
cout<<z;
}