堆排序:

/**
*
* 堆排序:
*
*/
public class HeapSort {

public void sort(int[] data) {
MaxHeap h = new MaxHeap();
h.init(data);
for (int i = 0; i < data.length; i++)
h.remove();
System.arraycopy(h.queue, 1, data, 0, data.length);
}

private static class MaxHeap {
void init(int[] data) {
this.queue = new int[data.length + 1];
for (int i = 0; i < data.length; i++) {
queue[++size] = data[i];
fixUp(size);
}
}

private int size = 0;

private int[] queue;

public int get() {
return queue[1];
}

public void remove() {
swap(queue, 1, size--);
fixDown(1);
}

// fixdown
private void fixDown(int k) {
int j;
while ((j = k << 1) <= size) {
if (j < size && queue[j] < queue[j + 1])
j++;
if (queue[k] > queue[j]) // 不用交换
break;
swap(queue, j, k);
k = j;
}
}

private void fixUp(int k) {
while (k > 1) {
int j = k >> 1;
if (queue[j] > queue[k])
break;
swap(queue, j, k);
k = j;
}
}

private void swap(int[] data, int i, int j) {
int temp = data[i];
data[i] = data[j];
data[j] = temp;
}
}
}