#include <cstdio>
#include <vector>
#define MOD 50000
using namespace std;

std :: vector <long long> Hash[50001];
int m;
long long x;
inline void add_to_Hash(int x){
    int L = x % MOD;
    Hash[L].push_back(x);
}
inline bool  check_Hash(int x){
    int L = x % MOD;
    vector<long long>:: iterator it;
    for(it = Hash[L].begin(); it != Hash[L].end() ; ++it)
        if(*it == x) return 1;
    return 0;
}
int main()
{
    freopen("dtcsu.in", "r", stdin);
    freopen("dtcsu.out", "w", stdout);
    for(int i = 1; i <= 276997 ; ++i){
        scanf("%lld", &x);
        add_to_Hash(x);
    }
    scanf("%d", &m);
    int Sol = 0;
    for(int i = 1; i <= m ; ++i){
        scanf("%d", &x);
        Sol = Sol + check_Hash(x);
    }
    printf("%d", Sol);
    return 0;
}