If this is going to be used for some game I wouldn't use an array, I would use a list because of the ease items can be added / removed.
Module Module1
Dim deck As New List(Of Integer)
Dim prng As New Random
Sub Main()
newDeck()
showDeck()
shuffle()
showDeck()
Dim s As String
Do
s = Console.ReadLine()
Select Case s
Case "s"
showDeck()
Case "c"
If deck.Count = 0 Then
Console.WriteLine("No cards")
Else
'take top card
Dim foo As Integer = deck(0)
deck.RemoveAt(0)
Console.WriteLine(foo.ToString)
End If
Case "n"
newDeck()
shuffle()
End Select
Loop Until s.ToLower = "x"
End Sub
Sub newDeck()
deck = Enumerable.Range(1, 52).ToList 'create deck
End Sub
Sub shuffle()
deck = deck.OrderBy(Function(r) prng.Next).ToList
End Sub
Sub showDeck()
Dim ctr As Integer = 0
Console.WriteLine()
For Each card As Integer In deck
Console.Write("{0}", card.ToString.PadLeft(4, " "c))
ctr += 1
If ctr Mod 10 = 0 Then Console.WriteLine()
Next
Console.WriteLine()
End Sub
End Module
For some time I have thought that this was a case where the computer shouldn't mimic the real world exactly. First, here is a program that shows the problem with knowing the seed of the random number generator.
'create a form with three buttons and a richtextbox
Dim deckIdx As New List(Of Integer)
Dim cards As New List(Of card)
Dim prng As New Random
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
newDeck()
shuffle()
showDeck()
End Sub
Private Sub Button3_Click(sender As System.Object, e As System.EventArgs) Handles Button3.Click
'show next five cards
Dim sb As New System.Text.StringBuilder
sb.AppendLine()
For x As Integer = 1 To 5
Dim foo As card = getTopCard()
If Not foo Is Nothing Then sb.AppendFormat("{0}", foo.theCard.ToString.PadLeft(4, " "c))
Next
RichTextBox1.AppendText(sb.ToString)
RichTextBox1.ScrollToCaret()
End Sub
Private Sub Form1_Shown(sender As Object, e As System.EventArgs) Handles Me.Shown
Button1.PerformClick()
End Sub
Class card
Public theCard As Integer
Public count As Integer
End Class
Sub newDeck()
prng = New Random(42) '<<<<<<<<<<<<<<<<<<<<<<<< OOPS!!!
deckIdx = Enumerable.Range(0, 51).ToList 'create deck indicies
cards = New List(Of card)
For Each cIDX As Integer In deckIdx
Dim foo As New card
foo.theCard = cIDX
foo.count = 0
cards.Add(foo)
Next
End Sub
Sub shuffle()
deckIdx = deckIdx.OrderBy(Function(r) prng.Next).ToList
End Sub
Function getTopCard() As card
If deckIdx.Count > 0 Then
Dim foo As New card
foo.theCard = cards(deckIdx(0)).theCard
foo.count = cards(deckIdx(0)).count
deckIdx.RemoveAt(0)
Return foo
Else
Return Nothing
End If
End Function
Sub showDeck()
Dim ctr As Integer = 0
Dim sb As New System.Text.StringBuilder
For Each card As Integer In deckIdx
sb.AppendFormat("{0}", cards(card).theCard.ToString.PadLeft(4, " "c))
ctr += 1
If ctr Mod 10 = 0 Then sb.AppendLine()
Next
RichTextBox1.Text = sb.ToString
End Sub
Running the program and pressing button1 / 3 repeatedly will produce the same results, over and over. If we are going to adhere to the idea that the computer must mimic the real world exactly, then the obvious fix is to not re-seed the PRNG. But what if we took a different approach.
Add this code
Dim bkgShuffle As Threading.Thread
Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click
Button2.Enabled = False
bkgShuffle = New Threading.Thread(AddressOf shuffleBkg)
bkgShuffle.IsBackground = True
bkgShuffle.Start()
End Sub
Sub shuffleBkg()
Do
Threading.Thread.Sleep(50)
shuffle()
Loop
End Sub
Run the program as before, press button 1 and 3 to verify that nothing has changed. When you are satisfied press button 2, and then press button 1 and 3.
When you play cards in person it is obvious that the deck is not constantly being shuffled, but what if it was? Would it change anything? If I play cards online do I know or care if the deck is constantly being shuffled?
The code was only to demonstrate a point, to think outside of the box, and should not be considered a finished product.
edit:
Bull Mountain is likely to affect some of this.
