User:Billmaths

This is billmaths from Beijing, China

Some info about me:
 * My info at PKU Judge Online: http://acm.pku.edu.cn/JudgeOnline/userstatus?user_id=billmaths
 * TopCoder Member Card: http://www.topcoder.com/tc?module=MemberProfile&cr=16169583

If you want to leave me a message, feel free to edit the discussion to this page.