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<?php class comparer { public static array $counter = []; public static function compare($a, $b) { static::$counter[$a] = (static::$counter[$a] ?? 0) + 1; static::$counter[$b] = (static::$counter[$b] ?? 0) + 1; return $a <=> $b; } } $a=[5,6,7,8,9,10,1,2,3,4]; uasort($a, 'comparer::compare'); var_dump(comparer::$counter);
Output for 8.1.32, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
array(10) { [5]=> int(5) [6]=> int(6) [7]=> int(2) [8]=> int(6) [9]=> int(2) [10]=> int(5) [1]=> int(5) [2]=> int(6) [3]=> int(6) [4]=> int(5) }
preferences:
56.79 ms | 406 KiB | 5 Q