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run code in 500+ PHP versions simultaneously
<?php $arr = [2,5,1,12,-5,4,-1,3,-3,20,8,7,-2,6,9]; $a = $arr; asort($a); $a = array_chunk($a, 5); $output = []; $idx = 0; while($a){ if($idx++ % 2){ $b = array_pop($a); arsort($b); }else{ $b = array_shift($a); } $output = array_merge($output, $b); } var_dump($output);
Output for 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.4, 8.3.6 - 8.3.30, 8.4.1 - 8.4.21, 8.5.0 - 8.5.7
array(15) { [0]=> int(-5) [1]=> int(-3) [2]=> int(-2) [3]=> int(-1) [4]=> int(1) [5]=> int(20) [6]=> int(12) [7]=> int(9) [8]=> int(8) [9]=> int(7) [10]=> int(2) [11]=> int(3) [12]=> int(4) [13]=> int(5) [14]=> int(6) }
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 array(15) { [0]=> int(-5) [1]=> int(-3) [2]=> int(-2) [3]=> int(-1) [4]=> int(1) [5]=> int(20) [6]=> int(12) [7]=> int(9) [8]=> int(8) [9]=> int(7) [10]=> int(2) [11]=> int(3) [12]=> int(4) [13]=> int(5) [14]=> int(6) }

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