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run code in 300+ PHP versions simultaneously
<?php $array = [ ['group' => 'A', 'A' => 1, 'B' => 2,], ['group' => 'B', 'A' => 3, 'B' => 4,], ['group' => 'A', 'A' => 5, 'B' => 6,], ['group' => 'B', 'A' => 7, 'B' => 8,] ]; $result = []; foreach ($array as ['group' => $group, $group => $result[$group][]]); var_export($result);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
array ( 'A' => array ( 0 => 1, 1 => 5, ), 'B' => array ( 0 => 4, 1 => 8, ), )
preferences:
91.05 ms | 407 KiB | 5 Q