Sub verification_check_digit()

Dim i_elec_num As String: i_elec_num = "42729022361510840736"

' i_elec_num = Selection

Dim i_str As String: i_str = Replace(i_elec_num, "-", "")
Dim i_len As Long: i_len = Len(i_str)
Dim i_mid As Long
Dim i_sum As Long

For i = 1 To i_len - 1
i_mid = CLng(Mid(i_str, i, 1))
If i Mod 2 = 0 Then
i_sum = i_sum + i_mid * 2
Else
i_sum = i_sum + i_mid * 1
End If
Next

'''debug.Print i_str, i_len, i_sum, i_sum Mod 10


End Sub