using System;

public class Program

{

    public static void Main()

    {

        //Q21P38

        int c,num2 ;

        Console.WriteLine("num1");

        int num1 = int . Parse ( Console . ReadLine());

​

            if (num1 >=100000&& num1<= 999999)

                for(int i=1;i<=6;i++)

                 c=0;

        if( (num1%10)+1==num2%10)

            c++;

        num /=10 ;

            else 

                Console .Write ("  invalid number ");

    }

}