You may see that in Codeforces Round #668 (Div. 1) and Codeforces Round #666 (Div. 1) and Codeforces Round #659 (Div. 1). Problem B are all game theory/conclusion problems. It seems that putting a conclusion problem on problem B has become a new trend.
Personally, I don't think it's very suitable that so many Div.1s have a game theory on B. Problems like this require thinking but is relatively much easier to write, sometimes 2~3 for's and if's may solve the problem, which makes no or little improvement to your abilities of writing programs. You can see that in large scale contests like CEOI or APIO or USACO, problemsetters tend to set problems that require both thinking and writing.
Make no offense, but I'd like to know what do those problemsetters think about it.