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<?php $myArray = array('x'=>'europe','y'=>'europe','a'=>'USA','b'=>'USA','c'=>'Canada'); $newList = array(); foreach($myArray as $key => $value){ if(array_key_exists($value, $newList)) array_push($newList[$value], $key); else $newList[$value][] = $key; } print_r($newList);
Output for 5.6.0 - 5.6.38, 7.0.0 - 7.0.32, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
Array ( [europe] => Array ( [0] => x [1] => y ) [USA] => Array ( [0] => a [1] => b ) [Canada] => Array ( [0] => c ) )
preferences:
146.38 ms | 404 KiB | 282 Q