heap sort
// @see https://www.youtube.com/watch?v=H5kAcmGOn4Q
function heapify(list, size, index) {
let largest = index;
let left = index * 2 + 1;
let right = left + 1;
if (left < size && list[left] > list[largest]) {
largest = left;
}
if (right < size && list[right] > list[largest]) {
largest = right;
}
if (largest !== index) {
[list[index], list[largest]] = [list[largest], list[index]];
heapify(list, size, largest);
}
return list;
}
function heapsort(list) {
const size = list.length;
let index = ~~(size / 2 - 1);
let last = size - 1;
while (index >= 0) {
heapify(list, size, --index);
}
while (last >= 0) {
[list[0], list[last]] = [list[last], list[0]];
heapify(list, --last, 0);
}
return list;
}
heapsort([4, 7, 2, 6, 4, 1, 8, 3]);