Imports System
Imports System.Text.RegularExpressions
Imports System.Collections.Generic
 
Public Class Test
	Public Shared Sub Main()
		Dim input As String = "c1 + 2c + cad + c1b"
	    Dim symbol As String = "\s*([-+*/=])\s*"
	    Dim numbers As String = "^[0-9]*\.?[0-9]+$"
	    Dim letters As String = "^[a-zA-Z_][a-zA-Z0-9_]*$"
 
	    Dim substrings() As String = Regex.Split(input, symbol)
 
	    For Each match As String In substrings
	        If Regex.IsMatch(match, symbol) Then
	            Console.WriteLine(match & " - operator")
	        ElseIf Regex.IsMatch(match, numbers) Then
	            Console.WriteLine(match & " - number")
	        ElseIf Regex.IsMatch(match, letters) Then
	            Console.WriteLine(match & " - identifier")
	        Else
	            Console.WriteLine(match & " - Invalid Identifier")
	        End If
	    Next
	End Sub
End Class

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