using System;

using System.Collections.Generic;

​

public class FairRandom {

    private int lastNumber = 3;   // we always need to know the last number generated

                                  // so it's a private field

    private Random rnd;           // we would also like to reuse the same Random object 

    /* this is a constructor */

    /*

    * a constructor will have these properties

    * 1. the constructor must have the same name of the Class

    * 2. a constructor can include different parameters

    * 3. you can not create a same constructor-parameters that existed alrady

            for calss A, you can not have 2 A() constructor, also you can not have 2 A(int x) constructor

            but you can have one A() and one A(int x) constructor in class A

    * 4. a constructor should be public, but you can also define other type in different situation

    */

    public FairRandom() {

         rnd = new Random();

    }

    public int Next() {

        int num;

        if (lastNumber == 6) {

            num = rnd.Next(1,3);

        }

        else if (lastNumber == 1) {

            num = rnd.Next(5,7);

        }

        else {

            num = rnd.Next(1,7); 

        }

        lastNumber = num;

        return num;

    }

}

​

public class Program

{

    public static void Main()

    {

        FairRandom rnd = new FairRandom();

        for (int i=0;i<100;i++)

            Console.WriteLine(rnd.Next());

    }

}