เขียนโปรแกรมจัดของเข้า section รบกวนช่วยแนะแนวทางด้วยค่ะ

Imports System.Collections.Generic
Imports System.Linq

Public Class LINQPermutation
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Dim dtTemp As New DataTable()

        dtTemp.Columns.Add("StringNum", GetType(String))
        dtTemp.Columns.Add("ListNo", GetType(Integer))

        dtTemp.Rows.Add(New Object() {"001", 0})
        dtTemp.Rows.Add(New Object() {"002", 1})
        dtTemp.Rows.Add(New Object() {"003", 2})
        dtTemp.Rows.Add(New Object() {"004", 3})
        dtTemp.Rows.Add(New Object() {"005", 4})
        dtTemp.Rows.Add(New Object() {"006", 5})
        dtTemp.Rows.Add(New Object() {"007", 6})
        dtTemp.Rows.Add(New Object() {"008", 7})
        dtTemp.Rows.Add(New Object() {"009", 8})
        dtTemp.Rows.Add(New Object() {"010", 9})

        Dim xxx = dtTemp.Rows(0).Field(Of Integer)("ListNo")
        Dim xxxx = Convert.ToInt32((System.Math.Floor(((xxx + 1) / 2) - 1) Mod 2) + 1)

        Dim query0 = From a In dtTemp Where a.Field(Of Integer)("ListNo") Mod 3 = 0
                     Join b In dtTemp
                     On a.Item("ListNo") Equals b.Item("ListNo") Where a.Item("ListNo") Mod 3 = 1

        Dim query1 = From a In dtTemp
                     Where a.Field(Of Integer)("ListNo") Mod 3 = 0
                     From b In dtTemp
                     Where b.Field(Of Integer)("ListNo") Mod 3 = 1
                     From c In dtTemp
                     Where c.Field(Of Integer)("ListNo") Mod 3 = 2

        Dim xyz = query1.Distinct

        Dim query2 = From a In dtTemp
                     Where a.Item("ListNo") Mod 3 = 1
        Dim query3 = From a In dtTemp
                     Where a.Item("ListNo") Mod 3 = 2

        Dim query = From a In query1
                    From b In query2
                    From c In query3
        'Where x.Item("ListNo") Mod 2 = 1
        '            From b In dtTemp
        '            Where (System.Math.Floor(((b.Field(Of Integer)("ListNo") + 1) / 2) - 1) Mod 2) + 1 = 2

        Dim querz = From a In dtTemp.AsEnumerable
                    Where (System.Math.Floor(((a.Item("ListNo") + 2) / 2) - 1) Mod 2) + 1 = 1
        Dim querb = From a In dtTemp.AsEnumerable
                    Where ((((a.Item("ListNo") + 2) / 2) - 1) Mod 2) + 1 = 1

        'MsgBox("xxx " & System.Math.Floor(51 / 50) Mod 50)
        'MsgBox(System.Math.Floor((49 / 50) Mod 50)) 
		'MsgBox(System.Math.Floor((50 / 50) Mod 50))
        'MsgBox(System.Math.Floor((99 / 50) Mod 50))
        'MsgBox(System.Math.Floor((100 / 50) Mod 50))
        'MsgBox(System.Math.Floor((249 / 50) Mod 50))
        'MsgBox(((((1 - 1) / 28) + 1) - 1) Mod 13)
        'Dim b = GetPermutationsXXX("987")
    End Sub

    Public Shared Function GetPermutationsXXX(ByVal s As String) As IEnumerable(Of String)
        If s.Length > 1 Then
            Return (From ch In s
                   From p In GetPermutationXXX(s.Remove(s.IndexOf(ch), 1))
                   Select String.Format("{0}{1}", ch, p))
        Else
            Return New String() {s}
        End If
    End Function
End Class