Public Class Form1
    '
    Dim ls As Integer           ' Länge der Speichen
    Dim ads As Integer          ' Anzahl der Speichen
    Dim adk As Integer          ' Anzahl der Kreuzungen
    Dim df As Integer           ' Durmesser Felge
    Dim bn As Integer           ' Breite Nabe
    Dim lk As Integer           ' Lochkreis Nabe
    '
    Dim df2 As Integer          ' bn2^2
    Dim bn2 As Integer          ' df2^2
    Dim lk2 As Integer          ' lk^2
    Dim acos As Integer         ' cos
    '
    Private Sub Rechnen_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Rechnen.Click
        '
        df = TextBox1.Text                  ' Innendurchmesser der Felge (590)
        df2 = df * df                       ' df^2
        bn = TextBox2.Text                  ' Breite der Nabe (71.6)
        bn2 = bn * bn                       ' bn^2
        lk = TextBox3.Text                  ' Lochkreis der Nabe (40)
        lk2 = lk * lk                       ' lk^2
        adk = TextBox4.Text                 ' Anzahl der Kreuzungen (3)
        ads = TextBox5.Text                 ' Anzahl der Speichen (36)
        acos = Math.Cos(720 * (adk / ads))  ' cosinus
 
        ls = Math.Sqrt(0.25 * (df2 + lk2 + bn2) - (2 * df * lk * acos))     ' 
        ' Speichenlänge
        laenge.Text = ls
        '
    End Sub

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Man kann Dreck nicht polieren!
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