leetcode总结 -- 对于一个给定的matrix，每个元素是0 or 1

Game of Life
bit manipulation
http://blog.csdn.net/xyqzki/article/details/50254081

Maximal Square
dp
http://blog.csdn.net/xyqzki/article/details/50252829

Maximal Rectangle
increasing stack
http://blog.csdn.net/xyqzki/article/details/50388287

Number of islands
using dfs/ bfs
http://blog.csdn.net/xyqzki/article/details/50330055