总是会忘记的一些东西， 找起来还怪费劲的，于是存到这里， OK。
============ Matrix67's blog ============
http://www.matrix67.com/blog/archives/276
十个利用矩阵乘法解决的经典题目
http://www.matrix67.com/blog/archives/813 用位运算生成下一个含有k个1的二进制数
==== 位运算（1~4） ====
http://www.matrix67.com/blog/archives/263
http://www.matrix67.com/blog/archives/264
http://www.matrix67.com/blog/archives/266
http://www.matrix67.com/blog/archives/268
============ 小HH's blog ============
线段树 http://www.notonlysuccess.com/index.php/segment-tree-complete/
插头DP http://www.notonlysuccess.com/index.php/plug-dp-complete/