<?php $word_file = file_get_contents("/usr/share/dict/words"); $words = explode("\n", $word_file); foreach($words as $key=>$word) { $word = strtolower($word); $last_letter = 0; for($i=0;$i<strlen($word);$i++) { $num_letter = ord($word[$i]); if($num_letter < $last_letter) unset($words[$key]); $last_letter = $num_letter; } } print_r($words); ?>