using System;                   

public class Program

{

    public static void Main()

    {

        int number; 

        int lastNum;

        string numberString;

        string lastNumString; 

        int invalid =0; 

        Console.Write("Enter a number: ");

        numberString= Console.ReadLine();

        if (Int32.TryParse(numberString, out number) ==true)

        {

            Console.Write("Enter a number: ");

            lastNumString= Console.ReadLine(); 

            if ((Int32.TryParse(lastNumString, out lastNum)== true))

            {

                    while (lastNum > number) 

                    {       

                        lastNum= number; 

                        Console.Write("Enter a number: ");

                        lastNumString= Console.ReadLine(); 

                        if (Int32.TryParse(lastNumString, out lastNum)== false)

                        {

                            //Console.WriteLine("invalid input.");

                            invalid = 1;

                            break;

                        }

                        else 

                        {

                        }

                    } 

                    if (invalid == 0)

                    {

                        Console.WriteLine("\nProgram Ends.");

                        Console.WriteLine("The input must be greater than the previous input.");

                    }

                    else 

                    {

                        Console.WriteLine("\nInvalid input.");

                    }

            }

            else 

            {

                Console.WriteLine("\nInvalid input.");

            }

        }

        else 

        {

            Console.WriteLine("\nInvalid input.");

        }

    }

}