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

namespace TestAbstract
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = "ZhangSan";
            ZhangSan A = new ZhangSan1();
            A.eat(s);
            Console.ReadLine();
            
        }
    }
    abstract public class Person
    {
        abstract public void eat(string s);
    }
    public class ZhangSan : Person
    {
        public override void eat(string s)
        { 
                Console.WriteLine(s);
        }
    }
    public class ZhangSan1 : ZhangSan
    {
        public override void eat(string s)
        {
            Console.WriteLine("ZhangSan1");
        }
    }
}