CS120 Day 8: Linked Lists; testing
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(really working with pointers and dynamic memory allocation)

LINKED LIST ===========================================


Basic Concept
- nodes contain data and links to neighboring nodes
- "head" of list is a reference to the first node (or null if empty)
- can dynamically increase and decrease as data is added and removed
- can add or delete with a few constant operations (no shifting)
    once the place in the list is found
- does not have random access to individual data elements like an array
- singly linked list with head pointer to first node is simplest form
- self-referential structures: each node points to another node which
    is the head of a (sub)list

head   |node1  |node2  |node3  ... |nodex  |nodeLast
  -->  |   --> |   --> |   --> ... |   --> |     null


http://en.wikipedia.org/wiki/Linked_list

code files: list.h, list.c, listDriver.c

- singly linked list
	- create list (insert at head, or insert at end)
	- add node to list (insert at head, or insert at end)
	- print list (forward)
	- clear list (must free memory!)
	- search & delete element functions
	- printReverse
- recursion works well, especially in C

- when passing to functions, if want pointer to change, must pass
	address of pointer (pointer to pointer)


Implementation Variations
- keep "tail" reference to the last node, makes adding to the end fast
- keep sentinel empty (dummy) nodes at beginning and end to avoid
    special cases in code
- make doubly linked list with forward and backwards links
- any combination of the above
- circular list: the last node points to the first


Testing
- blackbox - make sure all cases you need to handle are included
  - for linked list: several cases for all functions:
  	- empty list
	- not found/there
	- first node
	- last node
	- middle node
- whitebox - make sure all code statements are executed (gcov)
- both are very important!