Online PHP editor | refs for REQAa

<?php function mergeSort($array) { echo "array = " . json_encode($array) . "\n"; $count = count($array); if ($count == 1) { return $array; } $middle = $count / 2; // round/floor/ceil is unnecessary return merge( mergeSort(array_slice($array, 0, $middle)), mergeSort(array_slice($array, $middle)) ); } function merge($half1, $half2) { do { $temp[] = $half1[0] < $half2[0] ? array_shift($half1) : array_shift($half2); } while(isset($half1[0], $half2[0])); return array_merge($temp, $half1, $half2); } $input = [4, 2, 7, 5, 3]; $input = mergeSort($input); var_export($input);