using System;

public class Program

{

    public static void Main()

    {

        double d1 = 1.00000000000000001;

        double d2 = 1.00000000000000002;

        double d3 = 1.000000000000005; // See the output for d3

        if (d1 == d2) Console.WriteLine("Both double numbers are represented with the same bit combination");

        Console.WriteLine("d1 = " + d1);

        Console.WriteLine("d2 = " + d2);

        Console.WriteLine("d3 = " + d3);

        //Get a string from the user (this string represents a student’s major.)

        Console.WriteLine("What is your major?");

        string major = Console.ReadLine();

        //Get a number from a user (this number represents a student’s score.)

        Console.WriteLine("What is your score?");

        string input = Console.ReadLine();

        //Validate whether the score is a whole number.

        int score;

        bool ValidInt = int.TryParse(input, out score);

        //If not, show an error message.

                if (!ValidInt)

        {

        Console.WriteLine ("Score must be a whole number");

        return;//STOP

        }

        //Validate whether the score’s range is between 0 and 100.

        bool ValidRange = (score >= 0 && score <= 100);

         if (!ValidRange)

         {  

        //If not, show an error message.

        Console.WriteLine("Score range must be whole number between 0 and 100");

        return; //STOP

         }

        //

        //If not, show an error message. 

        //Show the following information based on the score

//Score: >= 90, show "You get A ".

//Score: 80 ~ 89, show "You get B ".

//Score: 70 ~ 79, show "You get C".

//Score: 60 ~ 69, show "You get D".

//Score: < 60, show "You get F".

//For an individual's score greater than 90, check his/her major

//Show "Congratulations! You are one of the best students in IS." if the major is "Information Systems"

//Show "Congratulations! You are one of the best students.” for other majors

    }

}