堆排序实现

#include <iostream>

void printArray(int theArray[], int n)
{
	for(int i = 0; i < n; i++)
	{
		std::cout << theArray[i] << " ";
	}
	std::cout << std::endl;
}

void adjustHeap(int theArray[], int n, int start)  //从start索引处结点开始调整 
{
	if(start < 0 || start >= n)
		return;
	int fatherIndex;
	int leftIndex;
	int rightIndex;
	int tmp;
	
	fatherIndex = start;
	leftIndex = 2 * fatherIndex + 1;        //start索引处结点的左孩子的索引 
	rightIndex = leftIndex + 1;             //start索引处结点的右孩子的索引 
	
	if(rightIndex < n)          //start索引处结点存在右孩子结点. 
	{
		if(theArray[fatherIndex] < theArray[rightIndex])     //右孩子结点大于start索引处结点 ，交换 
		{
			tmp = theArray[fatherIndex];
			theArray[fatherIndex] = theArray[rightIndex];
			theArray[rightIndex] = tmp; 
		}
	}
	if(leftIndex < n)       //start索引处结点存在左孩子结点，但不一定存在右孩子结点
	{
		if(theArray[fatherIndex] < theArray[leftIndex])     //右孩子结点大于左孩子结点树，交换 
		{
			tmp = theArray[fatherIndex];
			theArray[fatherIndex] = theArray[leftIndex];
			theArray[leftIndex] = tmp;
		}
	} 
	adjustHeap(theArray, n, start-1);         //再次递归调整start索引处的上一个结点 
}

void constructHeap(int theArray[], int n)
{
	int start = n / 2; 
	adjustHeap(theArray, n, start);                 //从length/2处开始调整 
}

void heapSort(int theArray[], int n)
{
	if(n == 1)                                    //当未排序序列中只剩一个元素时，直接跳出递归 
		return;
	int length = n;
	
	//printArray(theArray, length);              //打印出每次建立最大堆之后，数组排列情况 
	
	//将最大堆的堆顶元素与堆末尾元素交换，并取出该元素作为已排序数组元素 
	int tmp = theArray[0];                    
	theArray[0] = theArray[length-1];
	theArray[length-1] = tmp;
	 
	//再次调整交换后的堆，使得为满足最大堆 
	--length;                 //未排序序列长度减一 
	int start = length / 2;   
	adjustHeap(theArray, length, start);
	heapSort(theArray, length);             //递归进行堆排序 
}

int main(int argc, char *argv[]) {
	int myArray[] = {5,90,28,4,88,58,38,18,19,20};
	int length = sizeof(myArray) / sizeof(myArray[0]);
	constructHeap(myArray, length);
	heapSort(myArray, length);
	printArray(myArray, length);
	return 0;
}