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run code in 300+ PHP versions simultaneously
<?php $a = array ( 0 => array ( 866 => array ( 100355 => '0', ), ), 1 => array ( 866 => array ( 100844 => '0', ), ), 2 => array ( 866 => array ( 100586 => '0', ), ), ); var_export(array_column($a, 866));
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 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 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array ( 0 => array ( 100355 => '0', ), 1 => array ( 100844 => '0', ), 2 => array ( 100586 => '0', ), )

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