Tiger's leetcode solution

http://blog.sina.cn/dpool/blog/s/blog_5b9b4abe01017b4q.html

http://java67.blogspot.com/2012/12/producer-consumer-problem-with-wait-and-notify-example.html?m=1

Given the root of a binary tree, turn the tree upside down and return the new root . You can turn a binary tree upside down with the foll...

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. Implement the  MinStack  class: MinStack()...

. You will be given the number of pairs of parenthesis. Find out the total possible valid unique combinations and there should not be any du...

Q: from 1 to n, count the number of bits that were set to 1. For example, n == 1,  return 1, n == 2, return 3, n == 3, return 5 n==4, ...