Data commit

Task/ISBN13-check-digit/Visual-Basic-.NET/isbn13-check-digit.vb

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+Module Module1
+
+    Function CheckISBN13(code As String) As Boolean
+        code = code.Replace("-", "").Replace(" ", "")
+        If code.Length <> 13 Then
+            Return False
+        End If
+        Dim sum = 0
+        For Each i_d In code.Select(Function(digit, index) (index, digit))
+            Dim index = i_d.index
+            Dim digit = i_d.digit
+            If Char.IsDigit(digit) Then
+                sum += (Asc(digit) - Asc("0")) * If(index Mod 2 = 0, 1, 3)
+            Else
+                Return False
+            End If
+        Next
+        Return sum Mod 10 = 0
+    End Function
+
+    Sub Main()
+        Console.WriteLine(CheckISBN13("978-1734314502"))
+        Console.WriteLine(CheckISBN13("978-1734314509"))
+        Console.WriteLine(CheckISBN13("978-1788399081"))
+        Console.WriteLine(CheckISBN13("978-1788399083"))
+    End Sub
+
+End Module