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<?php $array = [ '2018-03-12' => [ 'United States' => 4, 'Australia' => 15, 'United Kingdom' => 0, 'New Zealand' => 0, ], '2018-03-13' => [ 'United States' => 0, 'Australia' => 8, 'United Kingdom' => 2, 'New Zealand' => 0, ] ]; foreach ($array as $key => $subarray) { $result[] = array_merge([$key], array_values($subarray)); } var_export($result);
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 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 - 8.3.27, 8.4.1 - 8.4.14
array ( 0 => array ( 0 => '2018-03-12', 1 => 4, 2 => 15, 3 => 0, 4 => 0, ), 1 => array ( 0 => '2018-03-13', 1 => 0, 2 => 8, 3 => 2, 4 => 0, ), )
preferences:
184.74 ms | 408 KiB | 5 Q