[Year 12 SofDev] DLTV Exam 1

[ATKINSON-BUCK, Damien]

Hi folks,
            I'm just going through the DLTV Exam and can't quite figure the answer to the algorithm question 12 below.
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My desk produces,
Pass

Middle

Low

High

Result

StudentNo(Middle)

1

0

1

999

False

1

2

1

0

999

False

125

3

0

1

999

False

1

4

1

0

999

False

125

AND SO ON


I've tried it as vb code below and ended in an infinite loop. Am I missing something blatantly obvious here or can anyone see the fix for this?

Module Module1
    Dim StudentNo() As Integer = {1, 125, 250, 375, 500, 625, 750, 875, 999}

    Sub Main()
        Dim low As Integer = 1
        Dim high As Integer = 999
        Dim result As Boolean = False
        Dim searchnum As Integer = 375

        Do While low <= high And result = False
            Dim middle As Integer = (low + high) Mod 2
            If StudentNo(middle) = searchnum Then
                result = True
                Dim myMessage As String = "Low " & low & ", High " & high & ", Mid " & middle
                MsgBox(myMessage, vbOK, "DONE")
            End If
            If StudentNo(middle) > searchnum Then
                high = middle
            Else
                low = middle
            End If
        Loop
    End Sub

End Module




Damien Atkinson-Buck
Head of Learning Area: Technology/Arts
p: +61 3 9490 3848

e: damien.atkinson-buck at ivanhoe.com.au<mailto:damien.atkinson-buck at ivanhoe.com.au>



f: +61 3 9490 3490

w: www.ivanhoe.com.au<http://www.ivanhoe.com.au>

w: www.ivanhoe100.com.au<http://www.ivanhoe100.com.au>

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