Online PHP editor | refs for lYob3

<?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);