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<?php $mainNumber = 6; $finalData = []; for ($i = 1; $i <= $mainNumber; ++$i) { $finalData[] = $mainNumber + (($i & 1 ? -1 : 1) * $i); } var_export($finalData);
Output for 7.1.25 - 7.1.27, 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 - 8.3.27, 8.4.1 - 8.4.14
array ( 0 => 5, 1 => 8, 2 => 3, 3 => 10, 4 => 1, 5 => 12, )
preferences:
158.7 ms | 407 KiB | 5 Q