Estructuras repetitivas Aprende programación con ejercicios C# Sharp

using System;
public class exercise37
{
    public static void Main()
    {
        int number, number2;
        int i;

        Console.Write("Enter first number: ");
        number = Convert.ToInt32(Console.ReadLine());

        Console.Write("Enter last number: ");
        number2 = Convert.ToInt32(Console.ReadLine());

        for (i = number; i <= number2; i++)
            Console.Write("{0} ", i);

        Console.WriteLine();

        i = number;
        while (i <= number2)
        {
            Console.Write("{0} ", i);
            i++;
        }
        Console.WriteLine();


        i = number;
        do
        {
            Console.Write("{0} ", i);
            i++;
        }
        while (i <= number2);

        Console.WriteLine();
    }
}