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<?php $mainNumber = 6; $finalData = []; $operator = '-'; for ($i = 1; $i <= $mainNumber; $i++) { switch ($operator) { case '-': $finalData[] = $mainNumber - $i; $operator = '+'; break; case '+': $finalData[] = $mainNumber + $i; $operator = '-'; break; } } print_r($finalData);
Output for 7.1.25 - 7.1.27, 7.2.0 - 7.2.16, 7.3.0 - 7.3.33, 7.4.11 - 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 )

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