using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace T6
{
    /// <summary>
    /// 动物抽象类
    /// </summary>
    abstract class Animal
    {
        /// <summary>
        /// 动物类的抽象方法
        /// </summary>
        public abstract void Breath();
    }
    /// <summary>
    /// 继承动物抽象类的人类
    /// </summary>
    abstract class Person : Animal
    {
        /// <summary>
        /// 人类的抽象方法
        /// </summary>
        public abstract void Study();
        public void Eating()
        {
            Console.WriteLine("Person吃饭.");
        }
    }
    /// <summary>
    /// 继承人类的黑人类
    /// </summary>
    class BlackMan : Person
    {
        /// <summary>
        /// 黑人类重写基类的Breath()方法
        /// </summary>
        public override void Breath()
        {
            //以下这句代码是自动生成的
            //throw new NotImplementedException();
            Console.WriteLine("BlackMan呼吸.");
        }
        /// <summary>
        /// 黑人类重写基类的Study()方法
        /// </summary>
        public override void Study()
        {
            //throw new NotImplementedException();
            Console.WriteLine("BlackMan学习.");
        }
        /// <summary>
        /// 使用new关键字隐藏基类的Eating()方法
        /// </summary>
        new public void Eating()
        {
            Console.WriteLine("BlackMan吃饭.");
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            BlackMan b = new BlackMan();
            b.Breath();
            b.Eating();
            b.Study();

            Console.WriteLine("-----------");
            Animal a = new BlackMan();
            a.Breath();

            Console.WriteLine("-----------");

            Person p = new BlackMan();
            p.Breath();
            p.Eating();
            p.Study();

            Console.Read();
        }
    }
}