KanoOnline.com Forum

:cry:  :cry:  :cry:  :cry:
Plzzzzzzzzzzzz my people, someone help me out here.

I have this VB .Net project on Stack,Queue and Linked List and I have NULL clue on how to do it.

So plz if ANYONE out there knows ANYTHING about these classes, plz holla at ur sista (who is desperate  :cry: )...Thank you

Note:

Stack adds/gets element to and from the front
Queue adds elements to the rear and removes from the front
Linked List do both (Stack and Queue)

and all the classes have methods to do the stuff. My instructor decided not to teach us this topic but THEN decided TO GIVE it to us as a PROJECT (worth 20% but now 15%).........so plz help me out.

Ikon God sai looking! yanzu da zeron ce ma da na ci  8)

Anyways...I have finally managed to do the project...and it's pretty cool  :o  -I like it

Oh Sista,

Have not been coming round for some time. I really could have helped even though may not be to your test. But nevertheless this is what I understand from your question for future reference.

A good student of Data Structures must understand these three functions very well before he answers his name.

In programming, there are three segments:

STACK segment
DATA segment
and CODE segment

STACK is where variables are stored. DATA is where information stocked in the program are stored. And the CODE segment iis where instructions are stored. All these are tarried by your computer during compilation process.

In the stack, items or variables are stored ONE on TOP of the OTHER. In programing terminolgy we call this process PUSH. That is to say Variables are PUSHED into the STACK. And during the programming execution Items are required to be retreived from the STACK for processing. The process is called POP. That is to say variable are POPED out from the STACK.

There are ways in which items can be PUSHED or POPED out in or out from the STACK. The first one as you say LILO Last In Last Out. Since the item you push unto the STACK will only go on top of the last item pushed. It invariably means it will be the one that will come out first whenever items are to be retrieved from the PILE of items in the STACK.

I have a good Turbo Pascal program that demonstrates how this one works. I will soon get the program and put it up here for your scrutiny and anybody who may wish to learn. Once you see the one on STACK you are  likely to be able to develop the one of QUEUE and LINK for yourself. You can even help convert the code to VB 6.0 for our learning.

Or pls you can get us that your project up here that we too can learn from your efforts.

Thank you once again.
Most grateful I remain

Quote from: "Ihsan"Ikon God sai looking! yanzu da zeron ce ma da na ci  8)

Anyways...I have finally managed to do the project...and it's pretty cool  :o  -I like it

To thank God (Alhamdulillah) share it with us, it will be apreciated.  :D

Hey Mr. Waz, I know you for this long but yet you did not give me anything about this Stack. You really a friend?????????????????????

:)
Thankx Waz...

Ok...here's the code (the CListNode is first implemented and then ClsList followed by others (Stack and Queue)

Public Class CListNode
   Private mData As Object
   Private mNextNode As CListNode

   Public Sub New(ByVal dataValue As Object, ByVal nextNodeValue As CListNode)
       mData = dataValue
       mNextNode = nextNodeValue
   End Sub

   Public Sub New(ByVal dataValue As Object)
       MyClass.New(dataValue, Nothing)
   End Sub

   Public ReadOnly Property Data() As Object
       Get
           Return mData
       End Get
   End Property

   Public Property NextNode() As CListNode
       Get
           Return mNextNode
       End Get
       Set(ByVal value As CListNode)
           mNextNode = value
       End Set
   End Property
End Class

*************************************************************

Public Class Clist
   Private mfirstNode As CListNode
   Private mlastNode As CListNode
   Sub New()

   End Sub

   Public Property firstNode() As CListNode
       Get
           Return MyClass.mfirstNode
       End Get
       Set(ByVal Value As CListNode)
           MyClass.mfirstNode = Value
       End Set
   End Property

   Public Property lastNode() As CListNode
       Get
           Return MyClass.mlastNode
       End Get
       Set(ByVal Value As CListNode)
           MyClass.mlastNode = Value
       End Set
   End Property

   Public Sub insertFront(ByVal itm As Object)
       Dim obj As CListNode = New CListNode(itm)

       If MyClass.isEmpty Then
           obj.NextNode = Nothing
           firstNode = obj
           lastNode = obj
       Else
           obj.NextNode = firstNode
           firstNode = obj
       End If

   End Sub

   Public Sub insertBack(ByVal itm As Object)
       Dim obj As CListNode = New CListNode(itm)

       If MyClass.isEmpty Then
           obj.NextNode = Nothing
           firstNode = obj
           lastNode = obj
       Else
           lastNode.NextNode = obj
           lastNode = lastNode.NextNode
       End If

   End Sub

   Public Function removeFront() As Object
       Dim CurrentNode As CListNode = firstNode.NextNode
       Dim PreviousNode As CListNode = firstNode

       If MyClass.isEmpty Then
           Return Nothing
       ElseIf lastNode Is firstNode Then
           firstNode = Nothing
           lastNode = Nothing
           Console.WriteLine("First item removed")
       Else
           PreviousNode = Nothing
           firstNode = CurrentNode
           Console.WriteLine("First item removed")
       End If

   End Function

   Public Function removeBack() As Object
       Dim CurrentNode As CListNode = firstNode
       Dim PreviousNode As CListNode = firstNode

       If MyClass.isEmpty Then
           Return Nothing
       ElseIf lastNode Is firstNode Then
           firstNode = Nothing
           lastNode = Nothing
           Console.WriteLine("Last item removed")
       Else
           Do While Not CurrentNode.NextNode Is Nothing
               PreviousNode = CurrentNode
               CurrentNode = CurrentNode.NextNode
           Loop
           lastNode = PreviousNode
           lastNode.NextNode = Nothing
           Console.WriteLine("Last item removed")
       End If

   End Function

   Public Sub makeEmpty()
       Do While Not MyClass.isEmpty
           MyClass.removeBack()
       Loop
       Console.WriteLine("Emptied")

   End Sub

   Public Function isEmpty() As Boolean
       Return firstNode Is Nothing
   End Function

   Public Sub display()
       Dim CurrentNode As CListNode = firstNode
       If isEmpty() Then
           Console.WriteLine("Empty")
       End If
       Do While Not CurrentNode Is Nothing
           Console.WriteLine(CStr(CurrentNode.Data))
           CurrentNode = CurrentNode.NextNode
       Loop
   End Sub
End Class

Public Class Cstack
   Inherits Clist
   Private mlist As Clist

   Public Sub New()
       List = New Clist
   End Sub

   Public Property List() As Clist
       Get
           Return mlist
       End Get
       Set(ByVal Value As Clist)
           mlist = Value
       End Set
   End Property

   Public Sub push(ByVal itm As Object)
       List.insertFront(itm)
   End Sub

   Public Sub pop()
       List.removeFront()
   End Sub

   Public Sub StkDisplay()
       List.display()
   End Sub

   Public Function top() As Object

       If List.isEmpty Then
           Console.WriteLine("The stack is empty")
       Else
           Return List.firstNode.Data
       End If

   End Function

   Public Function StkIsEmpty() As Object
       If List.isEmpty() Then
           Console.WriteLine("The stack is empty")
       End If
   End Function

   Public Sub StkMakeEmpty()
       List.makeEmpty()
   End Sub
End Class

**************************************************************************************************************************

Public Class Cqueue
   Inherits Clist
   Private mlist As Clist

   Public Sub New()
       List = New Clist
   End Sub

   Public Property List() As Clist
       Get
           Return mlist
       End Get
       Set(ByVal Value As Clist)
           mlist = Value
       End Set
   End Property

   Public Sub enqueue(ByVal itm As Object)
       List.insertBack(itm)
   End Sub

   Public Sub dequeue()
       List.removeFront()
   End Sub

   Public Function QisEmpty() As Object
       If List.isEmpty() Then
           Console.WriteLine("The Queue is empty")
       End If
   End Function

   Public Sub QMakeEmpty()
       List.makeEmpty()
   End Sub

   Public Sub Qdisplay()
       List.display()
   End Sub
End Class

**************************************************************************************************************************

Module Module1
   Dim choice As String
   Dim item As Object
   Dim stk As Cstack = New Cstack
   Dim qu As Cqueue = New Cqueue
   Dim lst As Clist = New Clist

   Sub Main()
       Console.WriteLine()
       Console.WriteLine("Main Menu")
       Console.WriteLine("Select your choice")
       Console.WriteLine("A: for stack")
       Console.WriteLine("B: for Queue")
       Console.WriteLine("C: for List")
       Console.WriteLine("D: to End")
       Try
           choice = Console.ReadLine
       Catch ex As Exception
           Console.WriteLine(ex.Message)
       End Try

       Select Case UCase(choice)
           Case "A"
               StackMethod()
           Case "B"
               QueueMethod()
           Case "C"
               ListMethod()
           Case "D"
               End
       End Select
   End Sub

   Private Sub StackMethod()
       Console.WriteLine()
       Console.WriteLine("Select the operation you would like to perform on the stack")
       Console.WriteLine("A: To add item to top of stack <Push>")
       Console.WriteLine("B: To remove item from the top of stack <Pop>")
       Console.WriteLine("C: To view the item on the top of the stack <Top>")
       Console.WriteLine("D: To clear the stack")
       Console.WriteLine("E: To display all the items in the stack")
       Console.WriteLine("F: To exit system")
       Console.WriteLine("G: To return to Main Menu")
       Console.WriteLine("H: To perform another operation on the stack")

       Try
           choice = Console.ReadLine
       Catch ex As Exception
           Console.WriteLine(ex.Message)
       End Try

       Select Case UCase(choice)
           Case "A"
               Console.WriteLine("Write the item you want to add to the top of the stack")
               item = Console.ReadLine
               stk.push(item)
           Case "B"
               stk.pop()
           Case "C"
               Console.WriteLine(stk.top())
           Case "D"
               Try
                   If CBool(stk.StkIsEmpty) Then
                       Err.Raise(3)
                   End If
               Catch When Err.Number = 3
                   Console.WriteLine("This is an empty Stack")
               End Try
               stk.StkMakeEmpty()
           Case "E"
               stk.StkDisplay()
           Case "F"
               End
           Case "G"
               Main()
           Case "H"
               StackMethod()
           Case Else
               Console.WriteLine("You have entered an invalid option")
       End Select
       StackMethod()
   End Sub
   Private Sub QueueMethod()
       Console.WriteLine()
       Console.WriteLine("Select the operation you would like to perform on the queue")
       Console.WriteLine("A: To add item to the end of the queue <Enqueue>")
       Console.WriteLine("B: To remove an item from the top of the queue <Dequeue>")
       Console.WriteLine("C: To Display all items in the queue")
       Console.WriteLine("D: To clear all the items in the queue")
       Console.WriteLine("E: To exit the system")
       Console.WriteLine("F: To return to Main Menu")
       Console.WriteLine("G: To perform another operation on the queue")
       Console.WriteLine()
       Try
           choice = Console.ReadLine
       Catch ex As Exception
           Console.WriteLine(ex.Message)
       End Try

       Select Case UCase(choice)
           Case "A"
               Console.WriteLine("enter the item u want to add to the queue")
               item = Console.ReadLine
               qu.enqueue(item)
           Case "B"
               qu.dequeue()
           Case "C"
               qu.Qdisplay()
           Case "D"
               Try
                   If CBool(qu.QisEmpty) Then
                       Err.Raise(3)
                   End If
               Catch When Err.Number = 3
                   Console.WriteLine("The list is already empty")
               End Try
               qu.QMakeEmpty()
           Case "E"
               Exit Select
           Case "F"
               Main()
           Case "G"
               QueueMethod()
           Case Else
               Console.WriteLine("You have entered an invalid option")
       End Select
       QueueMethod()
   End Sub
   Private Sub ListMethod()
       Console.WriteLine()
       Console.WriteLine("A: To add item to the top of the list")
       Console.WriteLine("B: To add item to the end of the list")
       Console.WriteLine("C: To remove item from top of the list")
       Console.WriteLine("D: To remove item from end of the list")
       Console.WriteLine("E: To delete all items in the list")
       Console.WriteLine("F: To Display all the items in the list")
       Console.WriteLine("G: To exit the system")
       Console.WriteLine("H: To return to Main Menu")
       Console.WriteLine("I: To perform another operation on the list")

       Try
           choice = Console.ReadLine
       Catch ex As Exception
           Console.WriteLine(ex.Message)
       End Try


       Select Case UCase(choice)
           Case "A"
               Console.WriteLine("enter the item u want to add to the front of the list")
               item = Console.ReadLine
               lst.insertFront(item)
           Case "B"
               Console.WriteLine("enter the item u want to add to the back of the list")
               item = Console.ReadLine
               lst.insertBack(item)
           Case "C"
               lst.removeFront()
           Case "D"
               lst.removeBack()
           Case "E"
               Try
                   If lst.isEmpty Then
                       Err.Raise(3)
                   End If
               Catch When Err.Number = 3
                   MsgBox("The list is already empty")
               End Try
               lst.makeEmpty()
           Case "F"
               lst.display()
           Case "G"
               End
           Case "H"
               Main()
           Case "I"
               ListMethod()
           Case Else
               Console.WriteLine("You have entered an invalid option")
       End Select
       ListMethod()
   End Sub
End Module

Yoruba Land ( Kola), you mean you've never seen dis prog. wid me in da office 2 yrs back???????????

Ihsan this is what I have in Pascal. I will take sometime study your codes in visual Basic. It is really a great thing  that we are learning here. Below is d code:

*************************************************************
Program Stak;
Uses
   Crt;
Const
   StackSize = 10;
Type
   StackItem = Record
      StName : String[15];
      Age    : Integer;
      Height : Real;
   End;
   Stack = Record
   Item  : Array[1..StackSize] of StackItem;
   Top   : Integer;
End;
Var
   Item : StackItem;
   S    : Stack ;
   Endprog : Boolean ;
   StackInit : Boolean;
Function Isempty(S: Stack): Boolean;
Begin
   If S.Top = 0 Then
      Isempty  := True
    Else
    Isempty := False
End;
Function StackFull(S:Stack) : Boolean;
Begin
   If S.Top > StackSize Then
      StackFull := True
   Else
   StackFull := False;
End;
Procedure Create(Var S:Stack);
Begin
   S.Top := 0
End;
Procedure  Add (I : StackItem ;Var S: Stack);
Const
   ErrorMessage  = 'Attempt to push into a full stack' ;
Begin
   S.Top := S.Top + 1 ;
   If StackFull(S) Then
   Begin
   Writeln(ErrorMessage);
   Readln;
   Exit;
   End Else
   S.Item[S.Top] := I
End;
Procedure Delete(Var S:Stack);
Const
   ErrorMessage = 'Attempt to pop an empty stack';
Begin
   If Isempty(S) Then
Begin
   Writeln(ErrorMessage);
   Readln;
   Exit;
End Else
   S.Top := S.Top - 1;
End;
Function MainMenu: Char;
Var
   Ch : Char;
Begin
   ClrScr;
   Writeln('1 . Push ');
   Writeln;
   Writeln('2 . Pop' );
   Writeln;
   Writeln('3 . Quit' );
   Repeat
      Ch := ReadKey;
     Until KeyPressed;
   MainMenu := Ch;
End;
Begin
   StackInit := False;
   Endprog := False;
   While Not Endprog Do
   Begin
      Case MainMenu of
      '1' : Begin
               Begin
                  ClrScr;
                  If not StackInit Then
                  Begin
                    Create(S);
                    StackInit  := True
                  End;
                With Item Do Begin
                           Write('Name:');
                           Readln(StName);
                           Write('Age:');
                           Readln(Age);
                           Write('Height:');
                           Readln(Height);
                          End;
                 Add(Item,s);
               End;
          End;
  '2' : Delete(S);
  '3' : Endprog := True;
Else
End;
End;
End.

Ihsan I definitely agree with your words.