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

9 votes263 views2 answers
Excel vba convert 2 Short integers to a Long integer
VBA
0 vote138 views1 answer
VB get external IP address
VBA
0 vote144 views2 answers
Excel vba number format file size
VBA
0 vote134 views1 answer
Vb net show lines for all axis labels in chart
VBA
0 vote132 views1 answer
Vba code for cutoff time
VBA
5 votes144 views1 answer
Excel vba left word from Long Integer
VBA
0 vote138 views1 answer
Vbnet hex to binary
VBA
0 vote148 views1 answer
Write listbox to text file vb.net
VBA
0 vote133 views1 answer
Excel vba send HTTP POST to server
VBA
1 vote143 views1 answer
Vbscript convert ascii code to character
VBA