June 2018 Update

Task/Roman-numerals-Decode/VBA/roman-numerals-decode.vba

@@ -0,0 +1,34 @@
+Option Explicit
+
+Sub Main_Romans_Decode()
+Dim Arr(), i&
+
+    Arr = Array("III", "XXX", "CCC", "MMM", "VII", "LXVI", "CL", "MCC", "IV", "IX", "XC", "ICM", "DCCCXCIX", "CMI", "CIM", "MDCLXVI", "MCMXC", "MMXVII")
+    For i = 0 To UBound(Arr)
+        Debug.Print Arr(i) & "   >>> " & lngConvert(CStr(Arr(i)))
+    Next
+End Sub
+
+Function Convert(Letter As String) As Long
+Dim Romans(), DecInt(), Pos As Integer
+
+    Romans = Array("M", "D", "C", "L", "X", "V", "I")
+    DecInt = Array(1000, 500, 100, 50, 10, 5, 1)
+    Pos = -1
+    On Error Resume Next
+    Pos = Application.Match(Letter, Romans, 0) - 1
+    On Error GoTo 0
+    If Pos <> -1 Then Convert = DecInt(Pos)
+End Function
+
+Function lngConvert(strRom As String) 'recursive function
+Dim i As Long, iVal As Integer
+
+    If Len(strRom) = 1 Then
+        lngConvert = Convert(strRom)
+    Else
+        iVal = Convert(Mid(strRom, 1, 1))
+        If iVal < Convert(Mid(strRom, 2, 1)) Then iVal = iVal * (-1)
+        lngConvert = iVal + lngConvert(Mid(strRom, 2, Len(strRom) - 1))
+    End If
+End Function