堆排序

#include <iostream>
#include <cstdio>
using namespace std;

void heapAdjust(int a[], int i, int sizeOfheap)//调整堆 (调整范围:i与i下面的子树)
{
int lchild = 2 * i;       //i的左孩子节点序号
int rchild = 2 * i + 1;   //i的右孩子节点序号
int maxs = i;             //先默认第i个是最大的
if(i <= sizeOfheap / 2)   //不调整叶子节点
{
if(lchild <= sizeOfheap && a[lchild] > a[maxs])
maxs = lchild;
if(rchild <= sizeOfheap && a[rchild] > a[maxs])
maxs = rchild;
if(maxs != i)
{
swap(a[i], a[maxs]);  //注意下标没换
heapAdjust(a, maxs, sizeOfheap); //避免调整之后以max为父节点的子树不是堆
}
}
}

void BuildHeap(int a[], int n)
{
int i;                       //非叶节点最大序号值为size/2
for(i = n / 2; i >= 1; i--)  //从下面往上面调整
heapAdjust(a, i, n);
}

void HeapSort(int a[], int n)
{
int i;
BuildHeap(a, n);
for(i = n; i >= 1; i--)
{
swap(a[1], a[i]);         //最后面的数和第一个数交换，结果最后一个数变为最大的树了
heapAdjust(a, 1, i - 1);
}
}

int main()
{
int sizeOfheap;
int a[100];
while(scanf("%d", &sizeOfheap) == 1 && sizeOfheap > 0)
{
int i;
for(i = 1; i <= sizeOfheap; i++)  //从下标1开始到n
scanf("%d", &a[i]);
HeapSort(a, sizeOfheap);
for(i = 1; i <= sizeOfheap; i++)
printf("%d ",a[i]);
printf("\n");
}
return 0;
}