using System;

​

public class Program

{

    public static void Main()

    {

        string restart = ("a");

        while (restart != "q")

        {

            Console.Clear();

            start:

                Console.WriteLine("how many square roots would you like to calculate?");

            string input = Console.ReadLine();

            double n;

            if (double.TryParse(input, out n))

            {

                if (n <= 0)

                {

                    Console.WriteLine("Please enter a positive number.");

                    goto start;

                }

                else

                {

                    double i = 1;

                    do

                    {

                        Console.WriteLine("the square root of: " + i + " is = " + Math.Sqrt(i).ToString("##.##"));

                        i++;

                    }

                    while (i <= n);

                    Console.WriteLine("press q to quit or anything else to restart.");

                    restart = Console.ReadLine();

                }

            }

            else

            {

                Console.WriteLine("please enter a postive number");

                goto start;

            }

        }

    }

}