using System;

using System.Collections.Generic;

using System.Text;

​

public class Program

{

    public static void Main()

    {

        StringBuilder pageSets = new StringBuilder();

        List<int> lstControlSheets = new List<int>()

        {1, 2, 5, 7, 8, 9, 11, 14, 15, 16, 17, 19, 21, 23, 25, 27, 29};

        int firstPage = 0, lastPage = 0, counter = 0;

        bool isFirstItemInSequence = true;

        //

        for (int i = 0; i < lstControlSheets.Count; i++)

        {

            if (isFirstItemInSequence)

            {

                firstPage = lstControlSheets[i];

                isFirstItemInSequence = false;

            }

​

            //

            if ((i + 1) < lstControlSheets.Count)

                lastPage = lstControlSheets[i + 1];

            //

            counter++;

            //

            if (lastPage - lstControlSheets[i] != 1)

            {

                isFirstItemInSequence = true;

                //

                if (counter == 1 && false)

                    pageSets.Append(String.Format("{0},", firstPage));

                else

                    pageSets.Append(String.Format("[{0}-{1}],", firstPage, lstControlSheets[i]));

                //

                counter = 0;

            }

        }

​

        //

        Console.Write(pageSets.ToString().Trim(new char[]{','}));

    }

}