S
想清楚了还没来得及写的题：
CF438D The Child and Sequence
P4171 [JSOI2010]满汉全席
CF285E Positions in Permutations
P2664 树上游戏
P4827 [国家集训队] Crash 的文明世界
P3313 [SDOI2014]旅行
P4314 CPU监控
CF979E Kuro and Topological Parity
CF827C DNA Evolution
CF886E Maximum Element
CF500F New Year Shopping
P3270 [JLOI2016]成绩比较
CF321E Ciel and Gondolas