doSort($a); $b = $this->doSort($b); if($a === $b){ return true; } return false; } function doSort($arr) { $len = count($arr); if($len <= 1){ return $arr; } for ($i = 0; $i < $len; $i++){ for ($j = $i + 1; $j < $len; $j++){ if($arr[$i] > $arr[$j]){ $tmp = $arr[$i]; $arr[$i] = $arr[$j]; $arr[$j] = $tmp; } } } return $arr; } } //test $a = "good"; $b = "odgo"; $model = new Solution(); var_dump($model->checkWord($a, $b));