Hide sequential values in VBA - arrays

Question

can you suggest me a routine - algorithm in VBA that can take the following String as an input:
"A14, A22, A23, A24, A25, A33"
and turn it to this:
"A14, A22 - A25, A33"
?
Thank you
EDIT:
Thanks to #omegastripes
Sub Test()
Dim strText, strRes, strTail, i
Dim comma As String: comma = ", "
Dim dash As String: dash = "-"
Dim delimiter As String
Dim counter As Integer
strText = "A14, A22, A23, A24, A25, A26, A33, A34"
strRes = ""
strTail = ""
With CreateObject("VBScript.RegExp")
.Global = True
.Pattern = "([a-zA-Z])(\d+)"
With .Execute(strText)
strRes = .Item(0).Value
For i = 1 To .Count - 1
If (.Item(i).SubMatches(0) = .Item(i - 1).SubMatches(0)) And (.Item(i).SubMatches(1) - .Item(i - 1).SubMatches(1) = 1) Then
counter = counter + 1
If counter > 1 Then
delimiter = dash
Else
delimiter = comma
End If
strTail = delimiter & .Item(i).SubMatches(0) & .Item(i).SubMatches(1)
Else
Debug.Print "strRes: " & strRes & ", " & "strTail: " & strTail & ", " & .Item(i).SubMatches(1)
strRes = strRes & strTail & ", " & .Item(i).SubMatches(0) & .Item(i).SubMatches(1)
strTail = ""
counter = 0
End If
Next
strRes = strRes & strTail
End With
End With
MsgBox strText & vbCrLf & strRes
End Sub

Answer 1

this should do
Function HideValues(inputStrng As String) As String
Dim outputStrng As String, iniLetter As String, endLetter As String
Dim vals As Variant, val As Variant
Dim iVal As Long, iniVal As Long, endVal As Long, diffVal As Long
vals = Split(WorksheetFunction.Substitute(inputStrng, " ", ""), ",")
iVal = 0
Do While iVal < UBound(vals)
iniVal = getValNumber(vals(iVal), iniLetter)
endVal = getValNumber(vals(iVal + 1), endLetter)
If iniLetter = endLetter Then
diffVal = 1
Do While endVal = iniVal + diffVal And iVal < UBound(vals) - 1
diffVal = diffVal + 1
iVal = iVal + 1
endVal = getValNumber(vals(iVal + 1), endLetter)
Loop
If diffVal > 1 Then
If iVal = UBound(vals) - 1 Then If endVal = iniVal + diffVal Then iVal = iVal + 1: diffVal = diffVal + 1
outputStrng = outputStrng & vals(iVal - diffVal + 1) & " - " & vals(iVal) & ","
Else
outputStrng = outputStrng & vals(iVal) & ","
End If
Else
outputStrng = outputStrng & vals(iVal) & ","
End If
iVal = iVal + 1
Loop
If iVal = UBound(vals) Then outputStrng = outputStrng & vals(iVal) & ","
HideValues = WorksheetFunction.Substitute(Left(outputStrng, Len(outputStrng) - 1), ",", ", ")
End Function
Function getValNumber(val As Variant, letter As String) As Long
Dim strng As String
Dim i As Long
strng = CStr(val)
For i = 1 To Len(strng)
If Mid(strng, i, 1) Like "[0-9]" Then Exit For
Next i
letter = Left(strng, i - 1)
getValNumber = CLng(Right(strng, Len(strng) - i + 1))
End Function
I tested it with the following:
Sub main()
Dim inputStrng As String
inputStrng = "A21, B22, C23, D24, E25, F26"
MsgBox inputStrng & vbCrLf & vbCrLf & "becomes" & vbCrLf & vbCrLf & HideValues(inputStrng)
inputStrng = "A21, A22, A23, A24, A25, A26"
MsgBox inputStrng & vbCrLf & vbCrLf & "becomes" & vbCrLf & vbCrLf & HideValues(inputStrng)
inputStrng = "A21, A22, A23, A24, A25, A33" '
MsgBox inputStrng & vbCrLf & vbCrLf & "becomes" & vbCrLf & vbCrLf & HideValues(inputStrng)
inputStrng = "A14, A22, A23, A24, A25, A33"
MsgBox inputStrng & vbCrLf & vbCrLf & "becomes" & vbCrLf & vbCrLf & HideValues(inputStrng)
inputStrng = "A14, A22, A23, A24, A25, A26"
MsgBox inputStrng & vbCrLf & vbCrLf & "becomes" & vbCrLf & vbCrLf & HideValues(inputStrng)
End Sub

Answer 2

Here is an example showing how you can hide sequential values with regex:
Option Explicit
Sub Test()
Dim strText, strRes, strTail, i
strText = "A14, A22, A23, A24, A25, A33"
strRes = ""
strTail = ""
With CreateObject("VBScript.RegExp")
.Global = True
.Pattern = "([a-zA-Z])(\d+)"
With .Execute(strText)
strRes = .Item(0).Value
For i = 1 To .Count - 1
If (.Item(i).SubMatches(0) = .Item(i - 1).SubMatches(0)) And (.Item(i).SubMatches(1) - .Item(i - 1).SubMatches(1) = 1) Then
strTail = "-" & .Item(i).SubMatches(0) & .Item(i).SubMatches(1)
Else
strRes = strRes & strTail & ", " & .Item(i).SubMatches(0) & .Item(i).SubMatches(1)
strTail = ""
End If
Next
strRes = strRes & strTail
End With
End With
MsgBox strText & vbCrLf & strRes
End Sub
And the output:

Answer 3

Roughly you can do it like this.
Sub Way()
Dim str1 As String
Dim cet As variant
Dim str2 As String
str1 = "A14, A22, A23, A24, A25, A33"
cet = split(str1, ",")
if len(join(cet)) > 2 then
str2 = cet(0) & "," & cet(1) & "-" & cet(Ubound(cet)-1) & "," & cet(ubound(cet))
End if
debug.Print str2
End Sub