Private Sub Quick_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Quick.Click
 
        n = Me.List.Items.Count
 
        Dim i As Long
        For i = 0 To n
            daten_sortiert(i) = daten(i)
        Next i
 
        'Call Quick_Sort(0, n, daten_sortiert)
        Call Quick_Sort(0, n, daten_sortiert)
 
        For i = 1 To n
            Me.ListQuickSort.Items.Add(daten_sortiert(i))
        Next i
 
    End Sub
 
    Private Sub Quick_Sort(ByVal l As Long, ByVal r As Long, ByVal a() As Long)
        Dim i As Long, j As Long, m As Long
        Dim t As Long
        i = l
        j = r
        m = a((l + r) \ 2)
        Do
            Do While a(i) < m
                i = i + 1
            Loop
            Do While m < a(j)
                j = j - 1
            Loop
            If i <= j Then
                t = a(i)
                a(i) = a(j)
                a(j) = t
                i = i + 1
                j = j - 1
            End If
        Loop Until i > j
        If l < j Then Quick_Sort(l, j, a)
        If i < r Then Quick_Sort(i, r, a)
 
    End Sub