Heap Sort Java Implementation

Heap Concept:

is a complete binary tree structure, divided into Dagen and small Gan, each non-leaf node is greater than (Dagen is greater than, small Gan thing less than) its two child nodes.

Heap Sort: The steps are divided into three stages:

1: Initialize large Gan (Keng Gen can also, this article takes Dagen as an example)

2: Swap heap top Max and array last,

3: Large-root heap adjustment for heap after swap position

4: Cycle through 2 steps, swap heap top and array second to last, third, etc. until the first place ...

Time Complexity Analysis:

Initialize heap sort structure time complexity requires N * LOGN

Maintenance of the new large-root heap complexity after each exchange is LOGN, N-Traversal switching, so the total time complexity: N * logn

The code is as follows

1  Packagecom.secbro.test;2 3 Importjava.util.Arrays;4 5  Public classHeapsort {6 7     //Test8      Public Static voidMain (string[] args) {9         int[] num = {10, 23, 17, 88, 39, 13, 11, 109, 108, 383, 100, 1, 10, 14};TenInitbuildheap (num, 0, num.length-1); OneSYSTEM.OUT.PRINTLN ("Initialize the big root heap:" +arrays.tostring (num)); A          for(inti = num.length-1; I >= 0; i--) { -Swap (num, 0, i); -Rebuildheap (num, 0, i); the         } -System.out.println ("Heap sort result:" +arrays.tostring (num)); -     } -  +     //Build Initialize large heap This step of time complexity is: N (LOGN) -     Private Static voidInitbuildheap (int[] num,intIndexintend) { +  A         if(num = =NULL|| Index >end) { at             return; -         } -          for(inti = end; I >= index; i--) { -             intParent = (i-1)/2; -             if(Num[i] >Num[parent]) { - swap (num, I, parent); in initbuildheap (num, index, i); -             } to         } +     } -  the     //Maintaining a new large-root heap structure *     Private Static voidRebuildheap (int[] num,intIndexintend) { $         if(num = =NULL|| Index >end) {Panax Notoginseng             return; -         } the         intleft = 2 * index + 1; +         intright = 2 * index + 2; A         if(Left < end && Num[index] <Num[left]) { the swap (num, index, left); + rebuildheap (num, left, end); -         } $         if(Right < end && Num[index] <Num[right]) { $ swap (num, index, right); - rebuildheap (num, right, end); -         } the     } - Wuyi     //Num[left] and Num[right] positions in the interactive array the     Private Static voidSwapint[] num,intLeftintRight ) { -         inttemp =Num[left]; WuNum[left] =Num[right]; -Num[right] =temp; About     } $}

Print results

Initialize the large root heap: [383, 109, 1, 108, 10, 1,,, 11, 13,, +, +,, 14, 17, 10, +, +/- 00, 108, 109, 383]

Heap Sort Java Implementation