[Unity][Heap sort]用Unity动态演示堆排序的过程(How Heap Sort Works)

[Unity][Heap sort]用Unity动态演示堆排序的过程

How Heap Sort Works

最近做了一个用Unity3D动态演示堆排序过程的程序。

I've made this app to show how heap sort works recently.

一图抵千言。

A picture paints a thousand words.

[Unity][Heap sort]用Unity动态演示堆排序的过程(How Heap Sort Works)

堆排序(Heap Sort)

堆排序总是建立这样一个二叉树：其父结点总大于其子结点。

Step 1: The first step of heap sort is to build a binary tree in which the parent node's value is always greater than its children nodes' value.

首先建堆。

It's called building the heap.

每轮将根结点与最后一个结点互换，然后对剩余部分建堆。

Step 2: Ater that, we swap the root node and the last node that hasn't been swapped yet.

Step 3: build the heap again like in step 1.

Step 4: if not all nodes are swapped in Step 2, goto Step2. Otherwise goto step 5.

Step 5: the heap sort is finished.

 1         private static void HeapSortAscending1<T>(this IList<T> arr)
 2             where T : IComparable
 3         {
 4             for (int i = arr.Count / 2 - 1; i >= 0; i--)
 5             {
 6                 arr.HeapAdjustAscending1(i, arr.Count);
 7             }
 8             for (int i = arr.Count - 1; i > 0; i--)
 9             {
10                 T temp = arr[0];
11                 arr[0] = arr[i];
12                 arr[i] = temp;
13                 arr.HeapAdjustAscending1(0, i);
14             }
15         }
16         private static void HeapAdjustAscending1<T>(this IList<T> arr, int nonLeafNodeToBeAdjusted, int unRangedCount)
17             where T:IComparable
18         {
19             int leftChild = nonLeafNodeToBeAdjusted * 2 + 1;
20             int rightChild = nonLeafNodeToBeAdjusted * 2 + 2;
21             int max = nonLeafNodeToBeAdjusted;
22             if (nonLeafNodeToBeAdjusted < unRangedCount / 2) // 是非叶节点(None leaf node)
23             {
24                 if (leftChild < unRangedCount && arr[leftChild].CompareTo(arr[max]) > 0)
25                 { max = leftChild; }
26                 if (rightChild < unRangedCount && arr[rightChild].CompareTo(arr[max]) > 0)
27                 { max = rightChild; }
28                 if (max!=nonLeafNodeToBeAdjusted)
29                 {
30                     T temp = arr[max];
31                     arr[max] = arr[nonLeafNodeToBeAdjusted];
32                     arr[nonLeafNodeToBeAdjusted] = temp;
33                     arr.HeapAdjustAscending1(max, unRangedCount);
34                 }
35             }
36         }

Heap sort