Change stack to Stack.
Change Stack to derive from Container.
Change queue to Queue.
Change Queue to derive from Container.
Add a test for Container.
Change list to ListNode.
Rename list to listnode.
Remove index.js
Add Heap.
Add chapter 5 exercises.
Use toString.
Add files for chapter 6.
Improve O(n) time O(1) space palindrome.
What a week