Question

after some codings i get a dynamic array like this. it may increase with more values according to data. but this following is a sample.

Array ( 
    [11-23-1] => 5 
    [17-29-2] => 5 
    [9-21-1] => 3 
    [10-52-2] => 5 
    [17-30-2] => 3
  )

after i get this array , i want to get the array in following format – with values of the above array as keys and the keys as value, with unique keys. like –

Array ( 
    5 => Array ( [0] => [11-23-1]
                 [1] => [17-29-2] 
                 [2] => [10-52-2] )

    3 => Array ( [0] =>[9-21-1] 
                 [1] => [17-30-2]) 
  )

how can i do it ??

Answer 1

reverse

$array = array ('11-23-1' => '5',
                '17-29-2' => '5',
                '9-21-1' => '3',
                '10-52-2' => '5',
                '17-30-2' => '3');

$newArray = array();            
foreach($array as $num => $one){
    $newArray[$one][] = $num;
}

var_export($newArray);