Compile and Execute C# Sharp Online

using System.IO;
using System;

class Sample
{  
    abstract class Mammal
    {  
        public abstract void walk();  
        public void sleep()  
        {  
            Console.WriteLine("any mammal can sleep");  
        }  
    }  
    class Human : Mammal  
    {  
        public override void walk()  
        {  
            Console.WriteLine("mammals can walk easily");  
        }  
    }  
    static void Main(string[] args)  
    {  
       Human M=new Human(); 
    
        M.walk();
        M.sleep();
    }  
}