using System;

​

public class Human

{

    public float height;

    public float weight;

    public float BMI

    {

        get

        {

            return weight / (height * height);

        }

    }

​

    public virtual int GetLegsCount ()

    {

        return 2;

    }

​

    public static float GetBMI (Human m)

    {

        return m.BMI;

    }

}

​

public class Lost1Leg : Human

{

    public override int GetLegsCount ()

    {

        return 1;

    }

}

​

public class Children : Human

{

    public string name;

​

​

​

    public override string ToString ()

    {

        return name;

    }

}

​

public class Student : Children

{

    public string className;

}

​

public class Program

{

    public static void Print (Human x)

    {

        Console.WriteLine(x);

        Console.WriteLine("Legs: " + x.GetLegsCount());

        Console.WriteLine("BMI:" + Human.GetBMI(x));

    }

​

    public static void Main ()

    {

        Human x = new Human();

        x.weight = 60;

        x.height = 1.6f;

        Print(x);

​

        Children z = new Children();

        z.name = "ZZZ";

        z.weight = 60;

        z.height = 1.4f;

        Print(z);

​

        Student y = new Student();

        y.name = "Abc";

        y.className = "10A";

        y.weight = 60;

        y.height = 1.8f;

        Print(y);

​

        Lost1Leg l = new Lost1Leg();

        l.weight = 60;

        l.height = 1.8f;

        Print(l);

​

    }

}