cd zack

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

public class Main {
    public static void main(String[] args) throws Exception {
        BufferedReader scan = new BufferedReader(new InputStreamReader(System.in));

        String line = scan.readLine();
        String[] parts = line.split(" ");
        int jack = Integer.parseInt(parts[0]);
        int jill = Integer.parseInt(parts[1]);

        HashSet<String> hSet = new HashSet<>();

        while (true) {
            int canSell = 0;
            ;
            for (int i=0; i<jack; i++) {
                String cd = scan.readLine();
                hSet.add(cd);

            }

            for (int i=0; i<jill; i++) {
                String cd = scan.readLine();
                if (hSet.contains(cd)){
                    canSell++;
                }
            }

            System.out.println(canSell);

            hSet.clear();

            line = scan.readLine();
            parts = line.split(" ");
            jack = Integer.parseInt(parts[0]);
            jill = Integer.parseInt(parts[1]);

            if (jack == 0 && jill == 0) {
                break;
            }
        }

    }

}