java数据结构和算法------堆排序

 1 package iYou.neugle.sort;
 2 
 3 public class Heap_sort {
 4     public static void HeapSort(double[] array) {
 5         for (int i = (int) Math.floor(array.length / 2); i > 0; i--) {
 6             HeapBuild(array, i, array.length);
 7         }
 8 
 9         for (int i = array.length - 1; i > 0; i--) {
10             double temp = array[0];
11             array[0] = array[i];
12             array[i] = temp;
13 
14             HeapBuild(array, 0, i);
15         }
16     }
17 
18     public static void HeapBuild(double[] array, int parent, int length) {
19         double temp = array[parent];
20         int child = parent * 2 + 1;
21         while (child < length) {
22             if (child + 1 < length && array[child + 1] > array[child]) {
23                 child++;
24             }
25             if (temp >= array[child]) {
26                 break;
27             }
28 
29             array[parent] = array[child];
30 
31             parent = child;
32             child = parent * 2 + 1;
33         }
34         array[parent] = temp;
35     }
36 }