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<?php $arr=array("aa", "az", "an","am", "ba", "by", "alien","i"); usort($arr, function ($a, $b) { return strlen($a) == strlen($b) ? $a <=> $b : strlen($a) <=> strlen($b); }); print_r($arr);

This is an error 500

Value for `_results` contains invalid data `array`


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