1, LinkedList
composed of one and one Node: [data][next].
[head] -> [data][next] -> [data][next] -> [data][next] -> [null].
Empty linkedList: head == null.
V.S. Array DS: fast at insert/delete.
[DS Basics] List,布布扣,bubuko.com
原文地址：http://www.cnblogs.com/chayu3/p/3928193.html
