vb code for Monty Hall problem not behaving in the desired way

Hi,

I have written a vb code for the Monte Hall Problem(in my case I have used the example of 3 cards - one of the card is red and 2 are black, you have to choose red to win) But I am not getting the desired results as expected.

Could someone point out my mistakes or advice me where I have gone wrong in my code.

I have attached my vb code with this thread.

vb.net Code:

Public Class Form2
 
    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 
        ThreeCardMonte()
 
    End Sub
 
    Sub ThreeCardMonte()
        Randomize()
        Dim cards(0 To 2) As Integer ' 1 means a red card , 0 means a black card anywhere in the 3 card stack
        Dim switchwins As Integer = 0
        Dim staywins As Integer = 0
        Dim winner_redcard As Integer
        Dim games As Integer
        Dim choice As Integer
        Dim shown_card As Integer
 
        For games = 1 To 100
            Randomize()
 
            winner_redcard = CInt(Int((2 * Rnd()) + 0))
            cards(winner_redcard) = 1 ' randomly place the winning red card in the card stack
            choice = CInt(Int((2 * Rnd()) + 0))
 
            Do
                shown_card = CInt(Int((2 * Rnd()) + 0))
            Loop While ((cards(shown_card) = 1) Or (shown_card = choice))
 
            staywins = staywins + Int(cards(choice))  ' the case where you won by staying with your choice
            Dim temp As Integer
            temp = choice + shown_card
            switchwins = switchwins + Int(cards(2 - (temp)))  ' the case where win by switching
            cards(winner_redcard) = 0 ' reset the winning card for the next round of game
        Next
 
        Debug.Print("Switchwins = ")
        Debug.Print(switchwins)
        Debug.Print("Staywins = ")
        Debug.Print(staywins)
 
    End Sub
End Class

Moved To VB.NET

is this not vb6? can you use rnd with .net :s

That's VB6 code: Debug.Print

-tg

"But I am not getting the desired results as expected." -- Ahh... the old eel toast problem... this is a classic problem around here. The problem is that you've got eels in your hovercraft. When this happens, is causes you get toast when you asked for OJ. Other known symptoms include the wheels falling off of your car, a door falling off its hinge, and worst of all an arm falling off.

We aren't mind readers, we can't possibly know what the expected results were supposed to be, and we have no way of knowing what the actual results were, so we couldn't tell you how to begin to fix it. Oh, wait... yes there is a way we can... put a break point on the first line, step through the code one line at a time, and check your values. Are they what they should be? Are they what you expect them to be? Does the logic flow properly?

-tg

Well if you just intuitively walk through the final results of the scenarios, you can save yourself alot of computing power

Code:

---

        Dim lose As Integer = 0, win As Integer = 0
        For x = 0 To 100000
            Dim r As New Random
            Dim winner As Integer = r.Next(1, 4)
            Dim pick As Integer = r.Next(1, 4)
            Dim shown As Integer = 0
            If winner = pick Then
                lose += 1
            Else
                win += 1
            End If
        Next
        MessageBox.Show("Wins: " & win & vbCrLf & "Loses: " & lose)

---

I am sorry for not letting you guys know what results I am expecting. I should be getting the number of switchwins as 2/3 of the total number of games played and number of staywins as 1/3 of total number of games played.

Also moderator this vb6 code , could you move it to the vb section ?
Thanks

What are you actually writting in? VB.NET or VB6? I see some of both in your code.

How do you get VB6 out of this?

Code:

---

Public Class Form2

Private Sub Form2_Load(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles MyBase.Load

---

I won't even go into the rest of the code.