以一段代码来看如何加注释，当然最重要的是你的实践！
参考 Robert.S 的《Algorithm》
/**
* 编译：
* 执行：
* 所依赖的库：StdOut.java
* 简介：找出最大元素的优先队列，使用二叉堆实现(以数组表示的完全二叉树作为data stru)
* ---------------------------------------------------------------------------
* Compilation: javac MaxPQ_byheap.java
* Execution: java MaxPQ_byheap
* Dependencies: StdOut.java
*
* Maximum-oriented PQ implementation using a binary heap(complete binary tree).
*/
package algs.implebyme.sorting;
import java.util.NoSuchElementException;
import algs.base.StdOut;
import algs.base.StdRandom;
/**
* 类的介绍：找出最大元素的优先队列，使用数组表示的完全二叉树来表征二叉堆。
* 方法：insert-插入元素；delMax-return当前队列中的最大元素。
* 实现细节：...
* 时间复杂度：...
* 空间复杂度：...
* 更多细节导航：
* 作者：@author yourname 2017.8.10
* 泛型 接口的说明：...
* --------------------------------------------------------------------
* The {@code MaxPQ_byheap} class represents ...
* It supports the usual insert and delMax operations.
* In order to let the client refer to ...
*
* It also supports methods for ...
*
* This implementation uses ...
*
* The insert, delMax operations take logarithmic time.
* Construction takes time proportional to the specified capacity.
*
* For additional documentation, see Section 2.4 of
* Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.
*
* @author Robert Sedgewick
* @author Kevin Wayne
*
* @param the generic type of key on this priority queue
*/
public class MaxPQ_byheap> {//??
private Key[] pq; //heap-ordered complete binary tree(not use pq[0])
private int N = 0; //number of items on priority queue
/**
* Initializes an empty priority queue with the given initial capacity.(方法功能intro)
* @param maxN the initial capacity of this priority queue(参数说明)
*/
public MaxPQ_byheap(int maxN){
pq = (Key[]) new Comparable[maxN+1];
}
/**
* Returns true if this priority queue is empty.
* @return {@code true} if this priority queue is empty;
* {@code false} otherwise
*/
public boolean isEmpty()
{
return N == 0;
}
/**
* Returns the number of items on the pq
* @return
*/
public int size()
{
return N;
}
/**
* Adds a new key to this priority queue.
* @param v the new key to add to this priority queue
*/
public void insert(Key v)
{
N++;
pq[N] = v;
swim(N);
}
/**
* Returns and delete a largest key on this priority queue.
* @return
* @throws NoSuchElementException if this priority queue is empty
*/
public Key delMax()
{
if (isEmpty()) throw new NoSuchElementException("Priority queue underflow");
Key max = pq[1]; // Retrieve max key from top.
exch(1, N--); // Exchange with last item.
pq[N+1] = null; // Avoid loitering.
sink(1); // Restore heap property.
return max;
}
/***************************************************************************
* Helper functions for compares and swaps.
***************************************************************************/
private boolean less(int i, int j){
return pq[i].compareTo(pq[j])<0;
}
private void exch(int i, int j){
Key t = pq[i];
pq[i] = pq[j];
pq[j] = t;
}
/***************************************************************************
* Helper functions to restore the heap invariant.
***************************************************************************/
private void swim(int k){
while (k > 1 && less(k/2, k))
{
exch(k/2, k);
k = k/2;
}
}
private void sink(int k){
while (2*k <= N)
{
//
int j = 2*k;
if (j < N && less(j, j+1)) j++;
if (!less(k, j)) break;
exch(k, j);
k = j;
}
}
// test
public static void main(String[] args) {
MaxPQ_byheap maxpq = new MaxPQ_byheap<>(30);
for(int i=0; i<30; i++){
maxpq.insert(StdRandom.uniform(50,800));
}
for(int i=0; i<30; i++){
StdOut.print(" "+maxpq.delMax());
}
}
}