using System;

using System.IO;

using System.Collections.Generic;

using System.Linq;

​

/*Write a program and ask the user to supply a list of comma separated numbers (e.g 5, 1, 9, 2, 10). If the list is empty or 

includes less than 5 numbers, display "Invalid List" and ask the user to re-try; otherwise, display the 3 smallest numbers in the list.*/

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Please enter a comma separated list greater than or equal to 5 numbers i.e. 5,1,9,2,10: ");

        string entry = Console.ReadLine();

        string[] entArr = entry.Split(',');

        while (entArr.Length < 5 || string.IsNullOrWhiteSpace(entry)) {

            Console.WriteLine("Invalid List; please retry");

            Console.WriteLine("Please enter a comma separated list greater than or equal to 5 numbers i.e. 5,1,9,2,10: ");

            entry = Console.ReadLine();

            entArr = entry.Split(',');

        }

        int[] iArray = new int[entArr.Length];

        for (int i = 0; i < entArr.Length; i++) {

            int n = Convert.ToInt32(entArr[i]);

            iArray[i] = n;

        }

        Array.Sort(iArray);

        Console.WriteLine("[" + iArray[0] + ", " + iArray[1] + ", " + iArray[2] + "]");

    }

}