优先队列（二叉堆实现) + 堆排序

public class Priority_queue {
private int[] a;
private int count;
Priority_queue(int[] b)
{
a = new int[b.length + 1];
for (int i = 1; i < a.length; ++i)
a[i] = b[i - 1];
count = b.length;
//形成堆
for (int k = count / 2; k >= 1; --k)
sink(k,count);
//a[0] for 哨兵  sentry
}
private void sink(int k,int N)
{
while (2 * k <= N)
{
int j = 2 * k;
while (j < N && a[j] < a[j + 1]) ++j;
if (a[k] > a[j]) break;
int temp = a[j];
a[j] = a[k];
a[k] = temp;
k = j;
}
}
private void swim(int k)
{
while (k > 1 && a[k] > a[k / 2])
{
int temp = a[k];
a[k] = a[k / 2];
a[k / 2] = temp;
k = k / 2;
}
}
public boolean isEmpty()
{
return count == 0;
}
private void resize(int n)
{
int[] temp = new int
;
for (int i = 1; i <= count; ++i)
temp[i] = a[i];
a = temp;
}
public Object deleteMax()
{
if (isEmpty())
return null;
int ret = a[1];
a[1] = a[count];
a[count--] = 0;
sink(1,count);
if (count == a.length / 4)
resize(a.length / 2);
return ret;
}
public boolean isFull()
{
return count == a.length - 1;
}
public void insert(int i)
{
if (isFull())
resize(2 * count);
a[++count] = i;
swim(count);
}
}

import edu.princeton.cs.algs4.StdOut;
import edu.princeton.cs.algs4.StdRandom;

public class HeapSort {
private int[] a;
public HeapSort(int N)
{
a = new int
;
for (int i = 0; i < N; ++i)
a[i] = StdRandom.uniform(-15*N,15*N);
}
public HeapSort(int[] b)
{
a = new int[b.length];
for (int i = 0; i < a.length; ++i)
a[i] = b[i];
}
public void sink(int k,int N)
{
while (2*k + 1 <= N)
{
int j = 2 * k + 1;
while (j < N && a[j] < a[j + 1]) ++j;
if (a[k] > a[j]) break;
int temp = a[j];
a[j] = a[k];
a[k] = temp;
k = j;
}
}
public void sort()
{
int N = a.length - 1;
for (int k = (N - 1) / 2; k >= 0; --k)
{
sink(k,N);
}
while (N >= 1)
{
int temp = a[0];
a[0] = a
;
a[N--] = temp;
sink(0,N);
}
}
public void display()
{
for (int i = 0; i < a.length; ++i)
StdOut.print(a[i] + " ");
StdOut.println();
}
}