VBA Sort RossetaCode

Public Sub Quick(a() As Variant, last As Integer)
' quicksort a Variant array (1-based, numbers or strings)
Dim aLess() As Variant
Dim aEq() As Variant
Dim aGreater() As Variant
Dim pivot As Variant
Dim naLess As Integer
Dim naEq As Integer
Dim naGreater As Integer
 
If last > 1 Then
    'choose pivot in the middle of the array
    pivot = a(Int((last + 1) / 2))
    'construct arrays
    naLess = 0
    naEq = 0
    naGreater = 0
    For Each el In a()
      If el > pivot Then
        naGreater = naGreater + 1
        ReDim Preserve aGreater(1 To naGreater)
        aGreater(naGreater) = el
      ElseIf el < pivot Then
        naLess = naLess + 1
        ReDim Preserve aLess(1 To naLess)
        aLess(naLess) = el
      Else
        naEq = naEq + 1
        ReDim Preserve aEq(1 To naEq)
        aEq(naEq) = el
      End If
    Next
    'sort arrays "less" and "greater"
    Quick aLess(), naLess
    Quick aGreater(), naGreater
    'concatenate
    P = 1
    For i = 1 To naLess
      a(P) = aLess(i): P = P + 1
    Next
    For i = 1 To naEq
      a(P) = aEq(i): P = P + 1
    Next
    For i = 1 To naGreater
      a(P) = aGreater(i): P = P + 1
    Next
End If
End Sub
 
Public Sub QuicksortTest()
Dim a(1 To 26) As Variant
 
 'populate a with numbers in descending order, then sort
 For i = 1 To 26: a(i) = 26 - i: Next
 Quick a(), 26
 For i = 1 To 26: Debug.Print a(i);: Next
 Debug.Print
 'now populate a with strings in descending order, then sort
 For i = 1 To 26: a(i) = Chr$(Asc("z") + 1 - i) & "-stuff": Next
 Quick a(), 26
 For i = 1 To 26: Debug.Print a(i); " ";: Next
 Debug.Print
End Sub

Source: rosettacode.org

Similar codes

1 vote71 views1 answer
Ms access open form to new record
VBA
3 votes115 views1 answer
Excel vba make long from two shorts
VBA
5 votes147 views1 answer
Excel vba get low byte from INTEGER
VBA
2 votes123 views1 answer
Excel vba check if string entirely numeric
VBA
31 votes232 views1 answer
Excel-vba how to convert a column number into an excel column
VBA
0 vote124 views1 answer
Vba get workbook name
VBA
0 vote124 views1 answer
Vba apostrophe chr
VBA
0 vote124 views1 answer
Vba collection contains
VBA
0 vote115 views1 answer
How to format a textbox as date vb net
VBA
0 vote119 views1 answer
Test if form is open vb
VBA