https://atcoder.jp/contests/abc055/tasks/abc055_b
https://atcoder.jp/contests/abc058/tasks/abc058_b
https://atcoder.jp/contests/abc073/tasks/abc073_c
https://atcoder.jp/contests/abc076/tasks/abc076_b
https://atcoder.jp/contests/abc090/tasks/abc090_b
https://atcoder.jp/contests/abc093/tasks/abc093_b
https://atcoder.jp/contests/abc189/tasks/abc189_b Alcoholic
https://atcoder.jp/contests/abc190/tasks/abc190_b Magic 3
https://atcoder.jp/contests/abc191/tasks/abc191_b Remove It
https://atcoder.jp/contests/abc193/tasks/abc193_b Play Snuke
https://atcoder.jp/contests/abc200/tasks/abc200_b 200th ABC-200
https://atcoder.jp/contests/abc203/tasks/abc203_b AtCoder Condominium
https://atcoder.jp/contests/abc204/tasks/abc204_b Nuts
https://atcoder.jp/contests/abc206/tasks/abc206_b Savings
https://atcoder.jp/contests/abc207/tasks/abc207_b Hydrate
https://atcoder.jp/contests/abc215/tasks/abc215_b log2(N)