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<?php $dates = [ [ ["2011-11-18 00:00:00" => 'C'], ["2011-11-18 00:00:00" => 'I'], ["2011-11-18 00:00:00" => 'S'], ], [ ["2011-11-22 00:00:00" => 'C'], ["2011-11-22 00:00:00" => 'S'] ] ]; var_export( array_reduce( $dates, fn($result, $set) => $result + [key($set[0]) => count($set)], [] ) );
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array ( '2011-11-18 00:00:00' => 3, '2011-11-22 00:00:00' => 2, )
preferences:
68.68 ms | 1114 KiB | 4 Q