2D array to 1D + bubble sort

[krazy07]

hi, i don't know the best way to do this but i have a question here:

i have a button on my form "display all customers". i now need to transfer all customers from the structured 2D array to the 1D array "customers"
and then sort this with a bubble sort.

*****Previous to this i made a 2D array with that has stored seats that are 10 rows and from A to J ( eg. A1 A2.....J2, J3)
I have then made code that allows you to add a customer name into the array and then display it. also having a button that removes that customer.

i have uploaded some of my code from the programs. i have left out my functions code as they work like the display seats, add customers and remove customers.

Interface


Code 1


Code 2


Code 3

[jmcilhinney]

Are you required to use a bubble sort by some assignment requirement or the like? If not then you should just use the Array.Sort method and then provide a Comparison delegate or IComparer object and let the Array class handle the sorting.

[krazy07]

yeah i have to use the dam bubble sort cause its required.

if u have a look at the pictures i have some sort of bubble sort happening.

i just don't no what the error in code is. and if Im on the right track thats all.

[jmcilhinney]

I don't much want to read code in screen shots. If you want to post code then include it in your post and wrap it in code tags. Other screen shots should just be attached directly to your post.

[krazy07]

lol its jus easy to jus click on the link aint it ?

[krazy07]

Public Class Form1
    Dim myArray(99) As seat
    Public Structure seat
        Dim seatNo As String
        Dim custName As String
    End Structure
    Dim seats(9, 9) As seat

    Private Sub mnuDisplaySeats_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuDisplaySeats.Click
        displaySeats()
    End Sub

    Private Sub mnuAddCust_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuAddCust.Click
        AddCust()
        displaySeats()
    End Sub

    Private Sub mnuRemoveCust_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuRemoveCust.Click
        RemoveCust()
        displaySeats()
    End Sub

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Load combo
        Dim letterNum As Integer
        Dim myStr As String

        For letterNum = Asc("A") To Asc("J")
            For seatNum As Integer = 1 To 10
                myStr = Chr(letterNum) & seatNum.ToString.Trim
                Me.cboSeats.Items.Add(myStr)
            Next
        Next
        Me.cboSeats.SelectedIndex = 0

        'load the 2d array
        Dim row, col As Integer
        Dim letter As Char
        Dim num As Integer = 65
        Dim str As String

        For row = 0 To 9
            letter = Chr(num)
            For col = 0 To 9
                str = letter & (col + 1)
                seats(row, col).seatNo = str
                seats(row, col).custName = "avail"
            Next
            str = ""
            num += 1
        Next
    End Sub

Here is the procedures to add the customer and so on

 Private Sub displaySeats()

        Dim row, col As Integer


        Dim seatStr As String = ""
        Dim custStr As String = ""

        Me.lstSeats.Items.Clear()

        For row = 0 To 9

            For col = 0 To 9

                seatStr = seatStr & seats(row, col).seatNo & Chr(9)

            Next
            Me.lstSeats.Items.Add(seatStr)
            seatStr = ""

            For col = 0 To 9
                custStr = custStr & seats(row, col).custName & Chr(9)
            Next
            Me.lstSeats.Items.Add(custStr)
            custStr = ""
        Next
    End Sub
    Private Sub AddCust()
        Dim row, col As Integer

        For row = 0 To 9
            For col = 0 To 9
                If seats(row, col).seatNo = cboSeats.SelectedItem And seats(row, col).custName = "avail" Then
                    seats(row, col).custName = txtCustomer.Text
                    MsgBox("Customer Has Been Added")

                    Exit Sub
                End If


            Next
        Next
        MsgBox("Customer spot has been taken")
    End Sub
    Private Sub RemoveCust()
        Dim row, col As Integer

        For row = 0 To 9
            For col = 0 To 9
                If seats(row, col).seatNo = cboSeats.SelectedItem And seats(row, col).custName = txtCustomer.Text Then
                    seats(row, col).custName = "avail"
                    MsgBox("Customer Has Been Removed")
                End If
            Next
        Next
    End Sub

Here is where i have trouble with my question

Private Sub lstSeats_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles lstSeats.SelectedIndexChanged

    End Sub

    Private Sub DisplayAllCustome*******tripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DisplayAllCustome*******tripMenuItem.Click

        bubbleSortArray(myArray)

        lstSeats.Items.Clear()
        For i As Integer = 0 To 99
            lstSeats.Items.Add(myArray(i).custName)
        Next

        'Dim temp As String
        'For passNum As Integer = 0 To 99

        '    For i As Integer = 0 To 100

        '        If seats(i - 1) > seats(0) Then
        '            temp = seats(i - 1)
        '            seats(i - 1) = seats(i)
        '            seats(i) = temp
        '        End If
        '    Next
        'Next
    End Sub
    Public Sub bubbleSortArray(ByVal inArray() As Integer)

        Dim temp As Integer


        Dim numPasses As Integer, numItems As Integer

        numPasses = inArray.GetUpperBound(0)
        numItems = inArray.GetUpperBound(0) + 1


        For passNum As Integer = 1 To numPasses

            For i As Integer = 1 To numItems - passNum

                If inArray(i - 1) > inArray(i) Then
                    temp = inArray(i - 1)
                    inArray(i - 1) = inArray(i)
                    inArray(i) = temp
                End If

            Next
        Next

    End Sub
End Class

[jmcilhinney]

So what exactly is the problem?

[krazy07]

ok well.
i no the chunks of code probably mean nothin to u and yeah.
well my problem is i have a button on my form "display all customers". i now need to transfer all customers from the structured 2D array to the 1D array "customers"
and then sort this with a bubble sort.

[jmcilhinney]

Yes, you already stated the aim and yes, you have also posted the code you have. Now what are we to do with it? You haven't told us what the actual problem is. Are we to read that code in the hope of something jumping out at us? We don't even know what we're looking for. You're saying "this is what I want to do, here's my code, fix it". That doesn't really cut it. You should be telling us how you're trying to do it and where it falls over.

[krazy07]

ok well. the error that comes up first is with the

"lstSeats.Items.Add(myArray(i).custName)" and the error is that not a member of Integer

and i dont no wat this error means .

thank you

[jmcilhinney]

Excellent, although it shouldn't take us 10 posts to get to the error message. If you want us to help with a compilation or run time error then the error message is the first thing you should be posting.

Here's the signature of your sorting method:

Public Sub bubbleSortArray(ByVal inArray() As Integer)

Now here's how you're calling it:

bubbleSortArray(myArray)

Now here's how you are declaring myArray:

Dim myArray(99) As seat

Do you see a compatibility problem there? You've written a method that will sort an array of Integers. That's nice, but how many Integer arrays have you got that you want sorted? None. You do have an array of Seats though, so wouldn't you need a method that sorts a Seat array?

[krazy07]

sorry about that.

so i should take the bubble sort(myarray) out ??

what im having trouble is with what should i be doing next. i understand what u mean but how to implement it

[jmcilhinney]

You written a method that accepts an array of Integers and sorts them by comparing each pair of Integers and swapping them if they are in the wrong order. That's no good for sorting Seat objects. You need to write a method that accepts an array of Seats and sorts them by comparing each pair of Seats objects and swapping them if they are in the wrong order.

Presumably comparing two Seat objects means comparing their SeatNo properties.

[krazy07]

ok i understand now

i no your not meant to give me complete slabs of code. but with the code stuff that you posted, what should i change from that. or should i add something completely new and add it to what i have ?


sorry if i sound like a complete noob. im just strugglin in VB at uni atm

[jmcilhinney]

You should change this:

Public Sub bubbleSortArray(ByVal inArray() As Integer)

to this:

Public Sub bubbleSortArray(ByVal inArray() As seat)

and then inside that method you need to compare seat objects instead of Integer values.

[krazy07]

ok thanks, when i do this tho more errors occur, they mayb simple fixes but here are the errors

Under the button -

        bubbleSortArray(myArray)   -error

        lstSeats.Items.Clear()
        For i As Integer = 0 To 99
            lstSeats.Items.Add(myArray(i).custName)    - error
        Next

And in the bubble sort -

        Dim temp As Integer


        Dim numPasses As Integer, numItems As Integer

        numPasses = inArray.GetUpperBound(0)
        numItems = inArray.GetUpperBound(0) + 1


        For passNum As Integer = 1 To numPasses

            For i As Integer = 1 To numItems - passNum

                If inArray(i - 1) > inArray(i) Then   -error
                    temp = inArray(i - 1)               -error
                    inArray(i - 1) = inArray(i)
                    inArray(i) = temp                     -error 
                End If

[jmcilhinney]

You're still comparing the elements of the array inside the bubbleSortArray method as though they were Integers. They are NOT Integers. They are Seat objects. You can't compare two Seat objects like this:

If inArray(i - 1) > inArray(i) Then

and you have declared the 'temp' variable as type Integer but you cannot assign a Seat object to an Integer variable like this:

temp = inArray(i - 1)

I will say this one last time: you have to write a method that takes a Seat array and then compares and sorts the seat objects it contains. The array does NOT contain Integers so you cannot compare the elements as Integers. Every element in the array is a Seat object so you have to compare them as Seat objects, NOT Integers.

[krazy07]

where can i get an example of a method that takes a Seat array and then compares and sorts the seat objects it contains

because im having trouble understanding

do i change these to all seat objects =

Dim temp As Integer


        Dim numPasses As Integer, numItems As Integer

 For passNum As Integer = 1 To numPasses

            For i As Integer = 1 To numItems - passNum

[jmcilhinney]

There is no example because it's your class. How could anyone else know how to sort an array of objects of a type that you created, or that your teacher created?

Think about this. Let's say that you have a line of people. I tell you to sort them by height using a bubble sort algorithm. What would you do? You'd work your way through the people in the line, comparing their height and swapping them if they were in the wrong order. At the end you'd have a line of people ordered by height. Now what if I said to reorder them by age? What would you do? You'd do the same thing but you'd compare the people's ages instead of their heights. Then what if I told you to to order them alphabetically by name? These are all easy things to do, right? Now, what if you had a line of seats and I told you to order them by seat number? That would be no more difficult would it?

Well, that's exactly what you do have, just in code instead of physically. That said, I am just assuming that sorting chairs means by seat number. You haven't actually told us.

[krazy07]

oh i must sound like a complete tool. anyway

its sorting by the customer. = custName i think

[krazy07]

also where have i gone wrong. can u see anywhere that stands out. and have i transfered it from 2D array to a 1D ??

[krazy07]

should i also change this

Public Sub bubbleSortArray(ByVal inArray() As seat)

to myArray as in under the display cust button it has

  bubbleSortArray(myArray)

[jmcilhinney]

Think it through. The point of the exercise is to sort an array of Seat objects customer name. You have to write a method to do the sorting. If it's going to sort a Seat array then it obviously has to take a seat array as a parameter. Inside that method you have to compare the Seat objects in the array in order to sort them. If they're supposed to be sorted by customer name then obviously you have to compare their custName properties. Finally, if this method takes a Seat array as a parameter then when you call it you obviously have to pass it a Seat array.

[krazy07]

Something like this ??

Private Sub mnuDisplaycust_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuDisplaycust.Click
        lstSeats.Items.Clear()

        arraytransfer()
        bubblesort()
        For i As Integer = 0 To 99
            If allcustomers(i).custName <> "Avail" Then


                lstSeats.Items.Add(allcustomers(i).custName & " " & allcustomers(i).seatNo)

            End If

        Next
        MsgBox("Scroll down for customers", MsgBoxStyle.Exclamation, "Heads-Up")

        'displays all the customers names that are not equal to avail.

    End Sub

  Private Sub bubblesort()
        Dim temp As seat
        For passNum As Integer = 1 To 100
            For i As Integer = 1 To 100 - passNum
                If (allcustomers(i - 1).custName > allcustomers(i).custName) Then
                    temp = allcustomers(i - 1)
                    allcustomers(i - 1) = allcustomers(i)
                    allcustomers(i) = temp

                End If
            Next
        Next
        'bubblesort rearranges all the customers in the array alphabetically
    End Sub

[jmcilhinney]

You appear to be on the right track.