#include <cstdio>
#include <unordered_set>
using namespace std;

unordered_set <long long> mySet;

int Q, nr;
long long X;

int main(){

    freopen("dtcsu.in" ,"r", stdin );
    freopen("dtcsu.out","w", stdout);

    for(int i = 1; i <= 276997; i ++){
        scanf("%lld", &X);
        mySet.insert(X);
    }

    scanf("%d", &Q);
    for(int i = 1; i <= Q; i ++){
        scanf("%lld", &X);

        if(mySet.count(X))
            nr ++;
    }

    printf("%lld\n", nr);

    fclose(stdin );
    fclose(stdout);

    return 0;
}