[2008] All combinations of 4 digit code

[Icyculyr]

I'm wonder if I had a code, say 9319, how could I get every possible combination of it, IE 9319, 9139, etc..

Cheers
Icyculyr

[alex_read]

Nested loops would do this.

For firstNumericDigit as integer = 0 to 9
  For secondNumericDigit as integer = 0 to 3
   ' .. Other loops here
      ' .. linkage of variable values and output here

[Icyculyr]

Thanks, it's not quite what I mean though, I want all possible combinations of specific 4 digit code, IE, every possible combination containing the numbers 9319, etc.. not every possible 4 digit combination

Cheers
Icyculyr

[Lerroy_Jenkins]

Well so far i have come up with this.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim A As Integer
        Dim B As Integer
        Dim C As Integer
        Dim D As Integer
 
        A = 1
        B = 2
        C = 3
        D = 4
 
        Label1.Text = A & B & C & D
        Label2.Text = A & B & D & C
        Label3.Text = A & C & B & D
        Label4.Text = A & C & D & B
        Label5.Text = A & D & B & C
        Label6.Text = A & D & C & B
        Label7.Text = B & A & C & D
        Label8.Text = B & A & D & C
        Label9.Text = B & C & A & D
        ' Etc Etc Etc
    End Sub

Now the thing I am not sure on, which you might be able to do is take the first number inside of a textbox say, and put that as A, and the second as B etc.

So A = Textbox1.text.(first) or what ever.

[Lerroy_Jenkins]

I had help on this, so I can not take all the credit.

But here you go.

A = TextBox1.Text.Substring(0, 1)
        B = TextBox1.Text.Substring(1, 1)
        C = TextBox1.Text.Substring(2, 1)
        D = TextBox1.Text.Substring(3, 1)

I have to give thanks to Mr Ludwig

[Lerroy_Jenkins]

Something else, you will get an error if you do not have 4 numbers. Plus you will get an error if you put letters inside. So.....

All of that into an If statement.

If Textbox1.Text.Length = 4 Then
 
' Do the code already given
 
Else
 
MsgBox("TextBox does not contain 4 digits!")
 
End If

[alex_read]

I love it - nice challenge! Good question that! Ok I *think* this works, appears to from a quick glance but I'll leave you to check all the combinations are there:

Public Class Form1
    Private _temporaryOutputString As String

    Private Sub Form1_Load(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Load
        Dim numericCodeOutputArrayList As New ArrayList
        Dim numericCodeInitArray(3) As String
        numericCodeInitArray(0) = "1" '"9"
        numericCodeInitArray(1) = "2" '"3"
        numericCodeInitArray(2) = "3" '"1"
        numericCodeInitArray(3) = "4" '"9"

        numericCodeOutputArrayList.Add(numericCodeInitArray(0))
        numericCodeOutputArrayList.Add(numericCodeInitArray(1))
        numericCodeOutputArrayList.Add(numericCodeInitArray(2))
        numericCodeOutputArrayList.Add(numericCodeInitArray(3))

        Dim firstOutputElementText As String = ""
        Dim secondOutputElementText As String = ""
        Dim thirdOutputElementText As String = ""

        For repositionFirstIndex As Integer = 0 To 3
            For repositionSecondIndex As Integer = 0 To 2
                For repositionThirdIndex As Integer = 0 To 1
                    OutputCurrentNumericCode(numericCodeOutputArrayList)

                    thirdOutputElementText = numericCodeOutputArrayList.Item(2)
                    numericCodeOutputArrayList.RemoveAt(2)
                    numericCodeOutputArrayList.Add(thirdOutputElementText)
                Next repositionThirdIndex

                secondOutputElementText = numericCodeOutputArrayList.Item(1)
                numericCodeOutputArrayList.RemoveAt(1)
                numericCodeOutputArrayList.Add(secondOutputElementText)
            Next repositionSecondIndex

            firstOutputElementText = numericCodeOutputArrayList.Item(0)
            numericCodeOutputArrayList.RemoveAt(0)
            numericCodeOutputArrayList.Add(firstOutputElementText)
        Next repositionFirstIndex
    End Sub

    Private Sub OutputCurrentNumericCodeToTextbox(ByRef numericCodeArrayList As ArrayList)
        _temporaryOutputString = numericCodeArrayList.Item(0)
        _temporaryOutputString &= numericCodeArrayList.Item(1)
        _temporaryOutputString &= numericCodeArrayList.Item(2)
        _temporaryOutputString &= numericCodeArrayList.Item(3)
        _temporaryOutputString &= Environment.NewLine
        TextBox1.Text &= _temporaryOutputString
    End Sub
End Class

[stanav]

Look in VB.Net code bank. I remember seeing a thread on creating unique combinations (permutation) there. With just 4 digits, it's OK to hard code it the way you do now, but imagine if you have 10 or more digits, you will not want to hard code it then

[Lerroy_Jenkins]

But he doesn't have 10 digits, I see where you are going with this true it would be a nightmare to hardcode all combinations of a 10 digits.

But he only wants 4, which is only a 2 min job to hardcode all those combinations.

[stanav]

But he doesn't have 10 digits, I see where you are going with this true it would be a nightmare to hardcode all combinations of a 10 digits.

But he only wants 4, which is only a 2 min job to hardcode all those combinations.

Didn't I say it's OK to hard code with only 4 digits?

[Lerroy_Jenkins]

Yes

I am just stuck on trying to work out how to stop an error being thrown up if the user puts in letters. My code works with Numbers.

And as for Alex's code..that went right over my head!

[stanav]

Yes

I am just stuck on trying to work out how to stop an error being thrown up if the user puts in letters. My code works with Numbers.

And as for Alex's code..that went right over my head!

How about using simple If's statement to check for the string.length first?

If userInput.Length >= 5 Then
   'Do something
Else
   MessageBox.Show("Input must be at least 5 character long!")
End If

[Lerroy_Jenkins]

Something else, you will get an error if you do not have 4 numbers. Plus you will get an error if you put letters inside. So.....

All of that into an If statement.

If Textbox1.Text.Length = 4 Then
 
' Do the code already given
 
Else
 
MsgBox("TextBox does not contain 4 digits!")
 
End If

This is what I have said a few posts ago, so I am checking that.

But all of my code only works for numbers, not letters.

[alex_read]

Ok ok I guess I can put in some comments, sorry!

I was storing the numbers in an arraylist as it has a remove() method. So 1st time it runs, the value is:
1234
After I print this, I store, then drop the 1st number using that removeat() method, so I get this:
234
and then I add that number to the end, so I get this:
2341
The loop runs round this procedure 4 times, each time dropping the 1st character, and appending it to the end to give:
1234
2341
3412
4123
The inner loops are doing the same thing, just on different characters - the 1st loop looks at the 2st character and worries about replacing that one, the 2nd loop does the same for the 2nd character out of the 4, and so-on if that makes sense...

[Lerroy_Jenkins]

That is very clever! I understand it a little better now.

I like my code better though.... Its simple... Just like me

[alex_read]

Thanks Quite a challenge and took a little while though! I noticed in the original, you had 2 of the same number there 9319 so the sample above will throw duplicates up (I was testing 1234 to make things easier in that one above). Here is a second sample for your scenario specifically, which removes the duplicates which the two 9 values create:

Public Class Form1
    Private _temporaryOutputString As String
    Private _temporaryOutputArrayList As ArrayList

    Private Sub Form1_Load(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Load
        Dim numericCodeOutputArrayList As New ArrayList
        Dim numericCodeInitArray(3) As String
        numericCodeInitArray(0) = "9"
        numericCodeInitArray(1) = "3"
        numericCodeInitArray(2) = "1"
        numericCodeInitArray(3) = "9"

        numericCodeOutputArrayList.Add(numericCodeInitArray(0))
        numericCodeOutputArrayList.Add(numericCodeInitArray(1))
        numericCodeOutputArrayList.Add(numericCodeInitArray(2))
        numericCodeOutputArrayList.Add(numericCodeInitArray(3))

        Dim firstOutputElementText As String = ""
        Dim secondOutputElementText As String = ""
        Dim thirdOutputElementText As String = ""
        _temporaryOutputArrayList = New ArrayList

        For repositionFirstIndex As Integer = 0 To 3
            For repositionSecondIndex As Integer = 0 To 2
                For repositionThirdIndex As Integer = 0 To 1
                    StoreCurrentNumericCode(numericCodeOutputArrayList)

                    thirdOutputElementText = numericCodeOutputArrayList.Item(2)
                    numericCodeOutputArrayList.RemoveAt(2)
                    numericCodeOutputArrayList.Add(thirdOutputElementText)
                Next repositionThirdIndex

                secondOutputElementText = numericCodeOutputArrayList.Item(1)
                numericCodeOutputArrayList.RemoveAt(1)
                numericCodeOutputArrayList.Add(secondOutputElementText)
            Next repositionSecondIndex

            firstOutputElementText = numericCodeOutputArrayList.Item(0)
            numericCodeOutputArrayList.RemoveAt(0)
            numericCodeOutputArrayList.Add(firstOutputElementText)
        Next repositionFirstIndex

        RemoveNumericCodeDuplicates(_temporaryOutputArrayList)
        OutputUniqueNumericCodes(_temporaryOutputArrayList)
    End Sub

    Private Sub StoreCurrentNumericCode(ByRef numericCodeArrayList As ArrayList)
        _temporaryOutputString = numericCodeArrayList.Item(0)
        _temporaryOutputString &= numericCodeArrayList.Item(1)
        _temporaryOutputString &= numericCodeArrayList.Item(2)
        _temporaryOutputString &= numericCodeArrayList.Item(3)
        _temporaryOutputString &= Environment.NewLine
        _temporaryOutputArrayList.Add(_temporaryOutputString)
    End Sub

    Private Sub RemoveNumericCodeDuplicates(ByRef storedNumericCodeArrayList As ArrayList)
        Dim currentlyEvaluatedElementText As String = ""
        Dim IsReadLoopOfArraylistComplete As Boolean = False
        Dim IsDuplicateRemovalLoopOfArraylistComplete As Boolean = False
        Dim storedNumericCodeElementIndex As Integer = 0
        Dim duplicateSearchElementIndex As Integer = 0

        Do Until storedNumericCodeElementIndex >= storedNumericCodeArrayList.Count
            currentlyEvaluatedElementText = _
              storedNumericCodeArrayList(storedNumericCodeElementIndex)
            duplicateSearchElementIndex = storedNumericCodeElementIndex + 1
            If currentlyEvaluatedElementText = 9139 Then
                Dim i As Integer = 1
            End If
            Do Until duplicateSearchElementIndex >= storedNumericCodeArrayList.Count
                If (storedNumericCodeArrayList(duplicateSearchElementIndex) = _
                currentlyEvaluatedElementText) Then
                    storedNumericCodeArrayList.RemoveAt(duplicateSearchElementIndex)
                    duplicateSearchElementIndex = duplicateSearchElementIndex - 1
                    If Not (storedNumericCodeElementIndex = 0) Then
                        storedNumericCodeElementIndex = storedNumericCodeElementIndex - 1
                    End If
                End If
                duplicateSearchElementIndex += 1
            Loop
            storedNumericCodeElementIndex += 1
        Loop
    End Sub


    Private Sub OutputUniqueNumericCodes(ByRef storedNumericCodeArrayList As ArrayList)
        For storedNumericCodeElementIndex = 0 To storedNumericCodeArrayList.Count - 1
            TextBox1.Text &= storedNumericCodeArrayList(storedNumericCodeElementIndex)
            'TextBox1.Text &= Environment.NewLine
        Next storedNumericCodeElementIndex
    End Sub
End Class

[Lerroy_Jenkins]

I had help on a different part of this code from "Shuja Ali".

But here is the end piece, this will give you all possible combinations for a 4 digit number.

Public Class Form1
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
 
        Dim A As Integer
        Dim B As Integer
        Dim C As Integer
        Dim D As Integer
 
        If IsNumeric(TextBox1.Text) Then
            If TextBox1.Text.Length = 4 Then
 
                A = TextBox1.Text.Substring(0, 1)
                B = TextBox1.Text.Substring(1, 1)
                C = TextBox1.Text.Substring(2, 1)
                D = TextBox1.Text.Substring(3, 1)
 
                Label1.Text = A & B & C & D
                Label2.Text = A & B & D & C
                Label3.Text = A & C & B & D
                Label4.Text = A & C & D & B
                Label5.Text = A & D & B & C
                Label6.Text = A & D & C & B
                Label7.Text = B & A & C & D
                Label8.Text = B & A & D & C
                Label9.Text = B & C & A & D
                Label10.Text = B & C & D & A
                Label11.Text = B & D & A & C
                Label12.Text = B & D & C & A
                Label13.Text = C & A & B & D
                Label14.Text = C & A & D & B
                Label15.Text = C & B & A & D
                Label16.Text = C & B & D & A
                Label17.Text = C & D & A & B
                Label18.Text = C & D & B & A
                Label19.Text = D & A & B & C
                Label20.Text = D & A & C & B
                Label21.Text = D & B & A & C
                Label22.Text = D & B & C & A
                Label23.Text = D & C & A & B
                Label24.Text = D & C & B & A
 
            Else
 
                MsgBox("TextBox does not contain 4 Numbers!")
            End If
 
        Else
 
            MsgBox("TextBox does not contain 4 Numbers!")
 
        End If
    End Sub
 
 
    Public Function IsNumeric(ByVal inputString As String) As Boolean
        Dim _isNumber As System.Text.RegularExpressions.Regex = New  _
        System.Text.RegularExpressions.Regex("(^[-+]?\d+(,?\d*)*\.?\d*([Ee][-+]\d*)?$)|(^[-+]?\d?(,?\d*)*\.\d+([Ee][-+]\d*)?$)")
        Return _isNumber.Match(inputString).Success
    End Function
End Class

[stanav]

This is what I have said a few posts ago, so I am checking that.

But all of my code only works for numbers, not letters.

So, in other words, you want to restrict the user to input only numeric values, right? If it's the case, there are various methods you can implement.

1. Use a NumericUpDown control instead of a TextBox. This is by far the easiest method because the control handles the filtering for you automatically, you don't have top write any additional code.

2. If you MUST use a TextBox, then you should handle the KeyPress event of the textbox and check to see if the inputted KeyChar is numeric. If it's not, you cancel the event. Search the forum for "numeric textbox" and you'll find some example.

3. Depending on what value type you're expecting to get from the user, use the TryParse method of that Type (i.e Integer.TryParse, Double.TryParse...), and if the TryParse returns false, you know that it's not a valid number.

[Kasracer]

I don't know about you guys but I had the same question for a homework assignment when I took a VB.Net course about 4 years ago. You may have done his homework for him.

[alex_read]

Drat. I wondered that, but I thought no - couldn't be as that was a hard one. Ohh well got caught out that time then.

[MaximilianMayrhofer]

This is pretty interesting. Here's what I came up with. It's totally dynamic, so it works with any number you input. But it is not the best method, only a quick and dirty one. It works on this principle:

Permute: 1234

Start with 1.

Take 2, and place it at every possible position in 1: 21, 12

Take 3, and place it at every possible position in the previous numbers: 321, 231, 213, 312, 132, 123

Take 4, and place it at every possible position in each of the previous numbers: 4321, 3421, 3241, 3214, 4231, 2431, 2341, 2314, ...

Continue indefinitely.

This takes approx. 10 seconds to calculate every permutation of a 9-digit number = 362880 permutations

Public Class Robust_Permutator
    'This list stores each number within the raw number
    Private Initial_Number_List As List(Of Integer)
    'This list stores the first number within the raw number, in order to pass it into the permutation function
    Private Initial_Permutations_List As List(Of Integer)

    Private Sub btn_Permutate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn_Permutate.Click
        'Initialise the lists
        Initial_Number_List = New List(Of Integer)
        Initial_Permutations_List = New List(Of Integer)

        'This loop loads all of the numbers within the raw number into the Number_List, starting from the second number
        For Number = 1 To txt_RawNumber.TextLength - 1
            Initial_Number_List.Add(Int16.Parse(txt_RawNumber.Text.Substring(Number, 1)))
        Next

        'Add the first number in the raw number to the Permutations_List to set it up
        Initial_Permutations_List.Add(Int16.Parse(txt_RawNumber.Text.Substring(0, 1)))

        'Disable the button
        btn_Permutate.Enabled = False

        'Make the progress bar visible
        prg_Permutations.Visible = True

        'Initialise the background worker
        bgr_Permutator.RunWorkerAsync()
    End Sub

    Private Sub txt_RawNumber_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txt_RawNumber.TextChanged
        'Enable the button if the value in the textbox is a number of at least 2 digits
        btn_Permutate.Enabled = (IsNumeric(txt_RawNumber.Text) And txt_RawNumber.TextLength > 1)
    End Sub

    Private Function Permutate(ByVal Worker As System.ComponentModel.BackgroundWorker, ByVal Numbers As List(Of Integer), ByVal Permutated_Combinations As List(Of Integer)) As String
        'Declare a background worker and assign it to the Worker parameter
        Dim bgrWorker As System.ComponentModel.BackgroundWorker = Worker
        'Declare a list and assign it to the Numbers parameter
        Dim Number_List As List(Of Integer) = Numbers
        'Declare a list and assign it to the Permutated_Combinations parameter
        Dim Permutations_List As List(Of Integer) = Permutated_Combinations

        'Declare a variable to record the current number of objects in the Permutations_List
        Dim Permutation_Count As Integer = Permutations_List.Count

        'Declare a variable to hold the currently selected Permutations_List number as a string
        Dim Current_Number As String
        'Declare a variable that will be manipulated and added to the Permutations_List
        Dim Temporary_Number As String

        'Loop through each of the original numbers in the Permutations_List
        For List_Index As Integer = 0 To Permutation_Count - 1
            'Convert the current number to a string for manipulation
            Current_Number = Permutated_Combinations(List_Index).ToString()
            'Loop through each position in the Current_Number
            For Place_Holder As Integer = 0 To Current_Number.Length
                'Assign the Current_Number to the Temporary_Number
                Temporary_Number = Current_Number
                'Insert the first number in the Number_List into the Temporary_Number string at the current position and add the new number to the Permutations_List
                Permutations_List.Add(Int64.Parse(Temporary_Number.Insert(Place_Holder, Number_List(0).ToString())))
            Next
        Next

        'Remove the first number in the Number_List
        Number_List.RemoveAt(0)

        'Loop through the Permutations_List until the last original number
        For List_Index As Integer = 0 To Permutation_Count - 1
            'Remove the first number in the list
            Permutations_List.RemoveAt(0)
        Next

        'Update the UI thread with the number of recursions left to go
        bgrWorker.ReportProgress(0, Number_List.Count)

        'Check whether there are any more numbers in the Numbers_List
        If Number_List.Count = 0 Then
            'Declare and initialise a new stringbuilder
            Dim Permutated_Numbers As New System.Text.StringBuilder
            'Loop through each number in the Permutations_List
            For List_Index As Integer = 0 To Permutations_List.Count - 1
                'Add the string representation to the stringbuilder
                Permutated_Numbers.AppendLine(Permutations_List(List_Index).ToString())
            Next
            'Return all of the permutated values
            Return Permutated_Numbers.ToString()
        Else
            'Call the function from itself
            Return Permutate(bgrWorker, Number_List, Permutations_List)
        End If
    End Function

    Private Sub bgr_Permutator_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles bgr_Permutator.DoWork
        'Declare a background worker and assign it to sender
        Dim Worker As System.ComponentModel.BackgroundWorker = DirectCast(sender, System.ComponentModel.BackgroundWorker)

        'The background worker returns the permutated values
        e.Result = Permutate(Worker, Initial_Number_List, Initial_Permutations_List)
    End Sub

    Private Sub bgr_Permutator_ProgressChanged(ByVal sender As System.Object, ByVal e As System.ComponentModel.ProgressChangedEventArgs) Handles bgr_Permutator.ProgressChanged
        'Update the progress bar value
        prg_Permutations.Value = (CDbl(txt_RawNumber.TextLength) - CDbl(e.UserState)) / CDbl(txt_RawNumber.TextLength) * 100
    End Sub

    Private Sub bgr_Permutator_RunWorkerCompleted(ByVal sender As System.Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles bgr_Permutator.RunWorkerCompleted
        'Fill the permutations textbox with the permutated values
        txt_Permutations.Text = DirectCast(e.Result, String)

        'Make the progress bar invisible
        prg_Permutations.Visible = False

        'Enable the button
        btn_Permutate.Enabled = True
    End Sub
End Class

[alex_read]

Might be a quick and dirty one but so were ours, I like the novel idea of the background worker for this, and making it generic. Was thinking of that when I hardcoded 4 loops in and wouldn't have been nice altering that way. Nice different take there! you too Leeroy Jenkins ??!! :P nothing wrong with keeping it simple - if it is homework or Icyculyr is at a novice level at the mo, then yours is the one which'll be used!

[Icyculyr]

Thanks for your replies...

>>It's not homework, nor am I a novice I just didn't want to spend time figuring it out -.- (nor did I have any)

Cheers
Icyculyr

[Lerroy_Jenkins]

lol, I am simple Makes it easier for me to understand until I am big and brainy like you guys lol.

And you lazy monkey Icyculyr! lol. '_'

[Icyculyr]

And you lazy monkey Icyculyr! lol. '_'

Haha, why be pro-active when I have a whole community of people to do things for me? LOL

I'm just joking, but seriously I was busy, I didn't have time, I was thinking how to calculate how many different combinations there was..

it's not 4^4, is it 4*4? I don't know..

Cheers
Icyculyr

[Lerroy_Jenkins]

1 Digit there is 1 combination

2 digits there are A B and B A combinations SO 2.

3 digits A B C, A C B, B A C, B C A, C A B, C B A. So 6 combinations

4 digits theres 24 combinations.

So we are going 1, 2, 6, 24. Can you see a pattern? Want me to work out 5 digits and their combinations?

[Lerroy_Jenkins]

Its simple. THe penny just dropped.

4 numbers to pick from (the user has put 4 numbers into the program) A B C D for example.

There are 4 possible options for the first choice.

There are then 3 possible options for the second choice.

There are then 2 possible options for the third choice.

And that leaves 1 possible option for the last choice.

So 4 * 3 * 2 * 1 = 24. 24 possibilities.

So to work out 5 possibilities 5 * 4 * 3 * 2 * 1 = 120.

6 possibilities = 6 * 5 * 4 * 3 * 2 * 1 = 720.

So you can work out how many possibilities there are. I wouldn't recomend hard coding for 5 digits +. 4 is easy, 5 and above is rediculouse.

[Icyculyr]

Thanks, that makes sense

Cheers
Icyculyr