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Random Numbers no repeats

Random Numbers no repeats

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dragonseyeangie	17 Nov, 2008 - 07:06 AM Post #1
New D.I.C Head Joined: 20 Oct, 2008 Posts: 23 My Contributions	Hello, I have an assignment that randomly generates 6 integers I'm not allowed to have any repeat numbers and am not sure how to code it so that it keeps from generating the same number twice for 6 times CODE Public Class Form1 Private rand As New Random Const intMAX_SUBSCRIPT As Integer = 5 Const intMAX_SUBSCRPT As Integer = 4 Dim intLottery(intMAX_SUBSCRIPT) As Integer Dim intPickSix(intMAX_SUBSCRIPT, intMAX_SUBSCRPT) As Integer Private Sub btnLottery_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnLottery.Click Dim intCount As Integer Dim intRandNum As Integer For intCount = 0 To intMAX_SUBSCRIPT intRandNum = rand.Next(55) + 1 intLottery(intCount) = intRandNum Next intCount lblNumOne.Text = intLottery(0) lblNumTwo.Text = intLottery(1) lblNumThree.Text = intLottery(2) lblNumFour.Text = intLottery(3) lblNumFive.Text = intLottery(4) lblNumSix.Text = intLottery(5) End Sub Private Sub btnPickSix_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPickSix.Click intPickSix(0, 0) = rand.Next(54) + 1 intPickSix(0, 1) = rand.Next(54) + 1 intPickSix(0, 2) = rand.Next(54) + 1 intPickSix(0, 3) = rand.Next(54) + 1 intPickSix(0, 4) = rand.Next(54) + 1 intPickSix(0, 5) = rand.Next(54) + 1 intPickSix(1, 0) = rand.Next(54) + 1 intPickSix(1, 1) = rand.Next(54) + 1 intPickSix(1, 2) = rand.Next(54) + 1 intPickSix(1, 3) = rand.Next(54) + 1 intPickSix(1, 4) = rand.Next(54) + 1 intPickSix(1, 5) = rand.Next(54) + 1 intPickSix(2, 0) = rand.Next(54) + 1 intPickSix(2, 1) = rand.Next(54) + 1 intPickSix(2, 2) = rand.Next(54) + 1 intPickSix(2, 3) = rand.Next(54) + 1 intPickSix(2, 4) = rand.Next(54) + 1 intPickSix(2, 5) = rand.Next(54) + 1 intPickSix(3, 0) = rand.Next(54) + 1 intPickSix(3, 1) = rand.Next(54) + 1 intPickSix(3, 2) = rand.Next(54) + 1 intPickSix(3, 3) = rand.Next(54) + 1 intPickSix(3, 4) = rand.Next(54) + 1 intPickSix(3, 5) = rand.Next(54) + 1 intPickSix(4, 0) = rand.Next(54) + 1 intPickSix(4, 1) = rand.Next(54) + 1 intPickSix(4, 2) = rand.Next(54) + 1 intPickSix(4, 3) = rand.Next(54) + 1 intPickSix(4, 4) = rand.Next(54) + 1 intPickSix(4, 5) = rand.Next(54) + 1 lstOutput.Items.Clear() lstOutput.Items.Add(intPickSix(0, 0) & " " & _ intPickSix(0, 1) & " " & _ intPickSix(0, 2) & " " & _ intPickSix(0, 3) & " " & _ intPickSix(0, 4) & " " & _ intPickSix(0, 5)) lstOutput.Items.Add("") lstOutput.Items.Add(intPickSix(1, 0) & " " & _ intPickSix(1, 1) & " " & _ intPickSix(1, 2) & " " & _ intPickSix(1, 3) & " " & _ intPickSix(1, 4) & " " & _ intPickSix(1, 5)) lstOutput.Items.Add("") lstOutput.Items.Add(intPickSix(2, 0) & " " & _ intPickSix(2, 1) & " " & _ intPickSix(2, 2) & " " & _ intPickSix(2, 3) & " " & _ intPickSix(2, 4) & " " & _ intPickSix(2, 5)) lstOutput.Items.Add("") lstOutput.Items.Add(intPickSix(3, 0) & " " & _ intPickSix(3, 1) & " " & _ intPickSix(3, 2) & " " & _ intPickSix(3, 3) & " " & _ intPickSix(3, 4) & " " & _ intPickSix(3, 5)) lstOutput.Items.Add("") lstOutput.Items.Add(intPickSix(4, 0) & " " & _ intPickSix(4, 1) & " " & _ intPickSix(4, 2) & " " & _ intPickSix(4, 3) & " " & _ intPickSix(4, 4) & " " & _ intPickSix(4, 5)) End Sub Private Sub btnClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClear.Click lblNumOne.Text = "0" lblNumTwo.Text = "0" lblNumThree.Text = "0" lblNumFour.Text = "0" lblNumFive.Text = "0" lblNumSix.Text = "0" lstOutput.Items.Clear() End Sub Private Sub btnExit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExit.Click Me.Close() End Sub Private Sub btnHelp_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnHelp.Click MessageBox.Show("Welcome to my simple Lottery Program." & ControlChars.CrLf & _ ControlChars.CrLf & "Please click the Help button to get help on the Simple " _ & "Lottery Program." & ControlChars.CrLf & ControlChars.CrLf & _ " Please click the Lottery button to generate/show six unique numbers " & _ "in the yellow boxes." & ControlChars.CrLf & ControlChars.CrLf & _ "Please click the Pick Six button to generate/show six unique numbers " & _ "in the list box." & ControlChars.CrLf & ControlChars.CrLf & _ "Enjoy!", "Lottery Help", MessageBoxButtons.OK, MessageBoxIcon.Information) End Sub End Class
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modi123_1	RE: Random Numbers No Repeats 17 Nov, 2008 - 07:49 AM Post #2
Suiter #2 Joined: 12 Jun, 2008 Posts: 1,216 Thanked: 49 times Dream Kudos: 150 My Contributions	Hmm.. get the number from the random generator. If that number exists in an array of arbitrary length get a new number. If not insert it into the array.
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magicmonkey

RE: Random Numbers No Repeats
17 Nov, 2008 - 08:40 AM

Post #3

D.I.C Regular

Joined: 12 Sep, 2008
Posts: 484

Windows

Thanked: 93 times
My Contributions

The quick and dirty method would be to loop until the random number generated is not in the array...


        Dim intCount As Integer
        Dim intRandNum As Integer

        'Warning: If intMAX_SUBSCRIPT >= 55 then the Do Loop will go into an endless loop
        If intMAX_SUBSCRIPT >= 55 Then Throw New Exception("Endless loop condition.")

        For intCount = 0 To intMAX_SUBSCRIPT
            Do
                intRandNum = rand.Next(55) + 1
            Loop Until Not intLottery.Contains(intRandNum)
            intLottery(intCount) = intRandNum
        Next intCount

A neat way would be to use a Generic HashSet(Of Integer) to add the numbers until the count = 6. A HashSet does not add duplicate numbers, so it is a clever way of accomplishing the task...


    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim DrawNumbers As List(Of Integer)
        DrawNumbers = RunDraw(6, 1, 55)
    End Sub

    Private Function RunDraw(ByVal DrawCount As Integer, ByVal DrawMin As Integer, ByVal DrawMax As Integer) As List(Of Integer)
        If DrawCount > DrawMax - DrawMin Then
            Throw New Exception("Draw count exceeds draw range.")
        End If

        Dim DrawNumbers As New Generic.HashSet(Of Integer)
        Dim RNG As New Random

        Do
            DrawNumbers.Add(RNG.Next(DrawMin, DrawMax + 1))
        Loop Until DrawNumbers.Count = DrawCount

        Return DrawNumbers.ToList
    End Function

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dbasnett	RE: Random Numbers No Repeats 17 Nov, 2008 - 08:47 AM Post #4
D.I.C Head Joined: 1 Oct, 2008 Posts: 224 Thanked: 13 times My Contributions	CODE Dim aRandom As New Random 'random number generator Dim aNumber As Integer 'a palce to store a random number Dim aRndL As List(Of String) aRndL = New List(Of String) Do While aRndL.Count < 6 aNumber = aRandom.Next(1, 57) 'pick a number from 1 - 56 inclusive If aRndL.IndexOf(aNumber.ToString) = -1 Then 'not picked aRndL.Add(aNumber.ToString) 'add it End If Loop This post has been edited by dbasnett: 17 Nov, 2008 - 08:49 AM
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