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<?php $levels = [4=>40]; $a = array_keys($levels); sort($a); $max = end($a); $toAdd = array_diff(array_keys(array_fill(1, $max, 0)), $a); $result = array_fill_keys($toAdd, 0); $merged = $levels + $result; ksort($merged); var_dump($merged);
Output for 7.1.0 - 7.1.33, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6
array(4) { [1]=> int(0) [2]=> int(0) [3]=> int(0) [4]=> int(40) }
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(4) { [1]=> int(0) [2]=> int(0) [3]=> int(0) [4]=> int(40) }

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