#Include <Array.au3>
#include <Constants.au3>

$s = FileRead("2.txt")

Local $w = StringRegExp($s, '(?is)(\b\w+\b)(?!.*\b\1\b)', 3)
_ArrayColInsert($w, 1)
For $i = 0 to UBound($w)-1
   StringRegExpReplace($s, '(?i)\b' & $w[$i][0] & '\b', $w[$i][0])
   $w[$i][1] = @extended

Next
_ArraySort($w, 1, 0, 0, 1)
_ArrayDisplay($w)