LP3317 [SDOI2014]重建
BZOJ2138 stone [Hall定理/线段树]
UOJ317 [NOI2017] 游戏 [2-SAT]
BZOJ5404 [HN集训2018] party [树链剖分/Hall定理/二分答案]
LOJ6062「2017 山东一轮集训 Day2」Pair [Hall定理/线段树]
LP2336 [SCOI2012] 喵星球上的点名 [SA/树状数组]
CF1042F Leaf Sets [DFS/贪心]