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run code in 300+ PHP versions simultaneously
<?php $a = [ '2019-09-28' => [ 'A' => 4, 'B' => 85, 'C' => 200 ], '2019-09-29' => [ 'A' => 5, 'B' => 83, 'C' =>202 ] ]; array_walk($a, function($v,$k) use (&$r){ array_walk($v,function($v1,$k1) use (&$r,$k){ $r[$k1][$k] = $v1; }); }); print_r($r);
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Array ( [A] => Array ( [2019-09-28] => 4 [2019-09-29] => 5 ) [B] => Array ( [2019-09-28] => 85 [2019-09-29] => 83 ) [C] => Array ( [2019-09-28] => 200 [2019-09-29] => 202 ) )
preferences:
102.91 ms | 408 KiB | 5 Q