import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.*;

public class Lesson {

    public static void main(String[] args) throws Exception {

        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        int countPrepod = Integer.parseInt(bufferedReader.readLine());
        TreeSet<Long> prepod = new TreeSet();
        for (int i = 0; i < countPrepod; ++i) {
            prepod.add(Long.parseLong(bufferedReader.readLine()));
        }

        int countStudent = Integer.parseInt(bufferedReader.readLine());
        ArrayList<Long> student = new ArrayList();
        for (int i = 0; i < countStudent; ++i) {
            student.add(Long.parseLong(bufferedReader.readLine()));
        }

        student.sort(((o1, o2) -> Long.compare(o1,o2)));
        int result=0;
        for (long find:prepod)
        {
                while (Collections.binarySearch(student,find)>=0)
                {
                    ++result;
                    student.remove(find);
                }
        }
        System.out.println(result);
    }

}