Online PHP editor | output for Q1IHC

<?php function roman2number($roman){ $conv = array( array("letter" => 'I', "number" => 1), array("letter" => 'V', "number" => 5), array("letter" => 'X', "number" => 10), array("letter" => 'L', "number" => 50), array("letter" => 'C', "number" => 100), array("letter" => 'D', "number" => 500), array("letter" => 'M', "number" => 1000), array("letter" => 0, "number" => 0) ); $arabic = 0; $state = 0; $sidx = 0; $len = strlen($roman); while ($len >= 0) { $i = 0; $sidx = $len; while ($conv[$i]['number'] > 0) { if (strtoupper(@$roman[$sidx]) == $conv[$i]['letter']) { if ($state > $conv[$i]['number']) { $arabic -= $conv[$i]['number']; } else { $arabic += $conv[$i]['number']; $state = $conv[$i]['number']; } } $i++; } $len--; } return($arabic); } $str = "This is IV chapter of book Hero and a preview of page MLCX"; echo preg_replace_callback('~\b[IVXLCDM0]+\b~', function($m) { return roman2number($m[0]); }, $str);