温故知新，基础复习（二叉堆排序）

温故知新，基础复习（二叉堆排序）

最小堆（最终数组的数据是降序），最大堆（最终数组的数据是升序）

下例是最小堆

#include <stdio.h>
#include <stdlib.h>

void Swap(int Arra[],unsigned int LeftIndex,unsigned int RightIndex)
{
	int TeampValue = Arra[LeftIndex];
	Arra[LeftIndex]=Arra[RightIndex];
	Arra[RightIndex]=TeampValue;
}

void MinHeapFixDown(int Arra[],unsigned int StartIndex,unsigned int ArraSize)
{
	int TeampValue = Arra[StartIndex];
	unsigned int MinValueIndexOfChild = 2*StartIndex+1;

	while(MinValueIndexOfChild<ArraSize)
	{
		//printf("%u,%d,%d,%d\n",StartIndex,TeampValue,MinValueIndexOfChild,ArraSize);
		if (MinValueIndexOfChild+1<ArraSize&&Arra[MinValueIndexOfChild]>Arra[MinValueIndexOfChild+1])
		{
			MinValueIndexOfChild=MinValueIndexOfChild+1;
		}

		if (Arra[MinValueIndexOfChild]>=TeampValue)
		{
			break;
		}

		Arra[StartIndex]=Arra[MinValueIndexOfChild];
		StartIndex=MinValueIndexOfChild;
		MinValueIndexOfChild=2*StartIndex+1;
	}

	Arra[StartIndex]=TeampValue;
}

void BuildMinHeap(int Arra[],unsigned int ArraSize)
{
	if (ArraSize<2)
	{
		return;
	}
	//printf("build start\n");
	for (unsigned int i = (ArraSize-1)/2+1; i >0; --i)
	{
		MinHeapFixDown(Arra,i-1,ArraSize);
	}
	//printf("build end\n");
}

void HeapSort(int Arra[],unsigned int ArraSize)
{
	BuildMinHeap(Arra,ArraSize);
	printf("ArraSize=%d\n",ArraSize);
	for (unsigned int i = ArraSize-1; i >=1; --i)
	{
		Swap(Arra,0,i);
		MinHeapFixDown(Arra,0,i);
	}
}

int main()
{
	//int Arra[]={-6,-8,9,-3,-1,0,13,-15,28,-40};
	int Arra[]={-6,10,-7,15,-9,12,50,-35,9};
	HeapSort(Arra,sizeof(Arra)/sizeof(Arra[0]));

	for (int i = 0; i < sizeof(Arra)/sizeof(Arra[0]); ++i)
	{
		printf("%d,",Arra[i] );
	}

	printf("\n");
}