Sorting algorithms/Heapsort: Difference between revisions

=={{header|D}}==

<lang d>import std.stdio, std.algorithm;

/// In-place HeapSort

public static void heapSort(Tseq)(Tseq seq) {

static void siftDown(Tseq seq, size_t start, size_t end) {

for (size_t root = start; root * 2 + 1 <= end; ) {

auto child = root * 2 + 1;

if (child + 1 <= end && seq[child] < seq[child + 1])

child++;

if (seq[root] < seq[child]) {

swap(seq[root], seq[child]);

root = child;

} else

break;

}

}

if (seq.length > 1)

for (size_t start = (seq.length - 2) / 2 + 1; start > 0; start--)

siftDown(seq, start - 1, seq.length - 1);

for (size_t end = seq.length - 1; end > 0; end--) {

swap(seq[end], seq[0]);

siftDown(seq, 0, end - 1);

}

}

void main() {

auto arr = [7, 6, 5, 9, 8, 4, 3, 1, 2, 0];

heapSort(arr);

writeln(arr);

}</lang>