Z2A vb 是否為15、33倍數

M5P01 判斷 S 是11的倍數、15的倍數、33的倍數

 變位1   M5P01-1 是否15倍數 , 可以被5整除也可以被3整除

    Function M5P01(ByVal s As String) As String

        Dim c As Char = Strings.Right(s, 1)

        If c<>"0" and c<>="5" then Return "N"  '最後1位非0非5

        ' 所有位數的總和是3的倍數？

        M5P01 = "Y"

        Dim sum As Integer = 0

        For i = 1 To s.Length

            sum += Val(Mid(s, i, 1))

        Next i

        If sum Mod 3 <> 0 Then Return "N"

    End Function

變位2   M5P01_2 是否33倍數 , 可以被11整除也可以被3整除

    Function M5P01_2(ByVal s As String) As String

        M5P01_2 = "Y"

        Dim odd As Integer = 0, even As Integer = 0

        For i = 1 To s.Length

            If i Mod 2 = 0 Then

                even += Val(Mid(s, i, 1))

            Else

                odd += Val(Mid(s, i, 1))

            End If

        Next

        If Math.Abs(odd - even) Mod 11 <> 0 Then Return "N" '非11倍

        If (odd + even) Mod 3 <> 0 Then Return "N" '非3倍

    End Function