using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        string mondayDesc = "Monday is first";

        string tuesdayDesc = "Tuesday is second";

        string wednesdayDesc = "Wednesday is third";

        string day = "tuesday";

        string dayDesc1 = null;

        if(day == "monday") {

            dayDesc1 = mondayDesc;

        } else if(day == "tuesday") {

            dayDesc1 = tuesdayDesc;

        } else if(day == "wednesday") {

            dayDesc1 = wednesdayDesc;

        }

        Console.WriteLine(dayDesc1);

        string dayDesc2 = null;

        switch(day) {

            case "monday":

                dayDesc2 = mondayDesc;

            break;

            case "tuesday":

                dayDesc2 = tuesdayDesc;

            break;

            case "wednesday":

                dayDesc2 = wednesdayDesc;

            break;

        }

        Console.WriteLine(dayDesc2);

        string dayDesc3 = null;

        Dictionary<string, string> dayDescMap = new Dictionary<string, string> {

            { "monday", mondayDesc },

            { "tuesday", tuesdayDesc },

            { "wednesday", wednesdayDesc }

        };

        dayDesc3 = dayDescMap[day];

        Console.WriteLine(dayDesc3);

    }

}