One of the NullCon vidoes talked about a marvalous Russian Gift. The Vidoe was uploaded on [May of 2015] What is the ID of that youtube video.
这题还是 Google, 搜索：may 2015 nullcon， 找到一个 油管的地址?v=a4_PvN_A1ts， flag: a4_PvN_A1ts
nullcom HackIM2016 -- Programming Question 4
原文：http://www.cnblogs.com/Christmas/p/5176439.html