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


public class CD {
    public static void main(String[] args) throws IOException{
        BufferedReader input = new BufferedReader(new InputStreamReader(System.in));

        while (true) {
            String command = input.readLine();
            if (command.startsWith("0 0")) break;

            String[] counts = command.split(" ");
            HashSet<String> jack_cds = new HashSet<String>();

            for (int i = 0; i < Integer.parseInt(counts[0]); ++i)
                jack_cds.add(input.readLine());

            int common = 0;
            for (int i = 0; i < Integer.parseInt(counts[1]); ++i)
                if (jack_cds.contains(input.readLine()))
                    common++;

            System.out.println(common);
        }
    }
}