Online PHP editor | refs for EKEaN

<?php $subjectSlots = [ "tamil" => [1, 2, 3, 4, 5], "english" => [4, 5, 6], "maths" => [1, 5, 8], "social" => [1, 2, 5], "pt" => [1], "hindi" => [3, 4, 7] ]; $requiredSubjects = ['tamil', 'tamil', 'pt', 'maths', 'maths', 'social', 'hindi', 'english']; usort($requiredSubjects, function($a, $b) use ($subjectSlots) { return $subjectSlots[$a] <=> $subjectSlots[$b]; }); var_export($requiredSubjects);