using System;

public class Program

{

    public static void Main()

    {

        var animal = Console.ReadLine();

        switch (animal)

{

  case "dog": Console.WriteLine("mammal"); break;

  case "crocodile":

  case "tortoise":

  case "snake": Console.WriteLine("reptile"); break;

  default: Console.WriteLine("unknown"); break;

}

​

    }

}