code

something interesting

http://www.computerbasedmath.org/

wolframalpha

blogs:

http://sillyrobot.ixiezi.com/index.php/archives/category/oi/oj-prob-sol/spoj

http://www.cnblogs.com/nyroro/articles/2459100.html

http://2hspsr.9966.org/index.asp?difficulty=0

fotile96：http://www.2333333.tk/

数论专场：http://blog.csdn.net/wxfwxf328/article/details/7611961

http://www.wutianqi.com/

http://crfish.blogbus.com/

SPOJ:

MSKYCODE VGCD LCMSUM GCDEX SEQAGAIN(带乘法和乘方的递推式) GCDSQF

BZOJ

[SCOI2012]奇怪的游戏 [JSOI]括号序列

tsin 楼房重建（树套数？）

DIVSUM

http://1tthinking.com/2011/03/22/%E7%A5%9E%E5%A5%87%E7%9A%84%E9%A2%84%E5%A4%84%E7%90%86

http://pan.baidu.com/share/link?shareid=154449&uk=688632126