Online PHP editor | refs for cOEXE

<?php $arr = Array ( '0' => array ( 'tenure' => '1 year to less than 2 years' ), '1' => array ( 'tenure' => '10 years to less than 15 years' ), '2' => array ( 'tenure' => '15 years or more' ), '3' => array ( 'tenure' => '2 years to less than 5 years' ), '4' => array ( 'tenure' => '5 years to less than 10 years' ) ); $res=[]; array_walk($arr, function($v, $k) use (&$res){ $key = substr($v['tenure'], 0, strspn($v['tenure'], "0123456789")); $res[$key] = $v; }); ksort($res); print_r($res);