242. Valid Anagram

class Solution {

    /**
     * @param String $s
     * @param String $t
     * @return Boolean
     */
    function isAnagram($s, $t) {
        $targets = str_split($s);
        $compares = str_split($t);
        foreach($targets as $target){
            $compareKey = array_search($target, $compares);
            if ($compareKey === false) {
                return false;
            }
            unset($compares[$compareKey]);
        }

        return empty($compares);
    }
}