import java.util.Scanner;
import java.util.Map.Entry;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int m = Integer.parseInt(scan.nextLine());
        int n = Integer.parseInt(scan.nextLine());
        HashMap<String, Integer> map = new HashMap<>();
        int max = 0;
        for (int i = 0; i < n; i++) {
            String[] strs = scan.nextLine().split(" ");
            int k = Integer.parseInt(strs[0]);
            if (k > 0) {
                String[] zus = new String[k];
                for (int j = 0; j < k; j++) {
                    StringBuilder sb = new StringBuilder();
                    sb.append(strs[2 * j + 1]);
                    sb.append(strs[2 * j + 2]);
                    zus[j] = sb.toString();
                }
                if (map.size() == 0) {
                    for (int j = 0; j < zus.length; j++) {
                        map.put(zus[j], 1);
                    }
                } else {
                    HashMap<String, Integer> map2 = new HashMap<>();
                    for (Entry<String, Integer> entry : map.entrySet()) {
                        int nums = entry.getValue();
                        for (int j = 0; j < zus.length; j++) {
                            if (entry.getKey().equals(zus[j])) {
                                nums++;
                                if (nums > max)
                                    max = nums;
                                map2.put(entry.getKey(), nums);
                                break;
                            }
                        }
                    }
                    map = new HashMap<>(map2);
                }
            } else {
                map = new HashMap<>();
            }
        }
        if (max <= 1)
            System.out.println(1);
        else
            System.out.println(max);
    }
}