//Solution By Omyrzak Meirambek
#include <iostream>
#include <fstream>
#include <cstdio>
#include <math.h>
#include <queue>
#include <stack>
#include <set>
#include <string>
#include <utility>
#include <cstdlib>
#include <algorithm>
#include <ctime>
#include <vector>
#include <map>
using namespace std;
#define fname ""
#define ull unsigned long long
#define ll long long
#define INF 1000*1000*1000
const int N = 20000;
map <int, int> q;
int n, x, res = 0, m;
int main ()
{
    #ifndef ONLINE_JUDGE
    freopen ("in","r",stdin);
    freopen ("out","w",stdout);
    #endif

    cin >> n;
    for (int i = 1; i <= n; i ++ ) {
        cin >> x;
        q[x] = 1;
    }
    cin >> m;

    for (int i = 1; i <= m; i ++ ) {
        cin >> x;
        res += q[x];
    }

    cout << res;

    return 0;
}