Lab 10: Priority Queues

CS61B

Representing a Tree With an Array

Working With Binary Heaps

Binary Heaps Defined

Difference between Binary Tree and Binary search trees:

source:
Difference between binary tree and binary search tree

Heap demo

Complete Trees

Writing Heap Methods

还是没解决open project出问题的情况，还是新建的Project，然后自己新建的java class.

做lab10过程中积累的一些零散的知识点：
1.ArrayList可以添加Null元素，例如

ArrayList<Integer> list = new ArrayList<>();
list.add(null)
System.out.println(list.size());
System.out.println(list.get(0));

Output:
1
null

2.ArrayList.add(Element e)是默认add到ArrayList的尾部

3.IndexOutOfBoundries Exception size = 9, index = 9 这个异常就是比如你的ArrayList的size是9，你用到了Index= 9.检查你哪里index弄错了。