using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("El mayor de 4 numeros");

        //Declarar variables

        int a,b,c,d;

        //Solicitar 

        Console.WriteLine("Introducir el valor de a,b,c,d");

        //Leer

         a=Convert.ToInt32(Console.ReadLine());

         b=Convert.ToInt32(Console.ReadLine());

         c=Convert.ToInt32(Console.ReadLine());

         d=Convert.ToInt32(Console.ReadLine());

        //Calcular

        //Si a es mayor que b

        if (a>b)

        { //Si es mayor

            //Si a es  mayor c

            if (a>c)

            //Si a es mayor d

            if (a>d)

            {

             Console.WriteLine("El mayor es a"+ a);

            }else

            {

             Console.WriteLine("El mayor es b"+b);

            }

        }else

        {

          if(b>c)

          {

           Console.WriteLine("El mayor es c "+c);

          }else

          {

                 Console.WriteLine("El mayor es c"+c);

          }

        }

    }

}