#include <iostream>
#include <fstream>
#include <unordered_map>
#include <set>
#include <iomanip>
#include <algorithm>
#include <bitset>
#include <cstring>
#include <cstdio>
using namespace std;

ifstream fin("dtcsu.in");
ofstream fout("dtcsu.out");

long long nums[276998];

int numsLen;

bool isFound(long long number) {
    int left = 1, right = numsLen;
    while (left < right) {
        int m = (left + right) / 2;
        if (nums[m] < number) {
            left = m + 1;
        } else {
            right = m;
        }
    }
    return nums[left] == number;
}

int main() {
    ios_base::sync_with_stdio(false);
    fin.tie(NULL);
    for (int i = 1; i <= 276997; ++i) {
        long long number;
        fin >> number;
        nums[++numsLen] = number;
    }
    sort(nums + 1, nums + numsLen + 1);
    int q;
    fin >> q;
    int ans = 0;
    for (int i = 1; i <= q; ++i) {
        long long number;
        fin >> number;
        if (isFound(number)) {
            ++ans;
        }
    }
    fout << ans;
    return 0;
}