====== 2020牛客暑期多校训练营（第十场） ====== ===== Results ===== ==== Summary ==== * Solved 7 out of 12 problems * Rank 32/1041 in official records * Solved 8 out of 12 afterwards
#Who=PenaltyABCDEFGHIJDirt
11大吉大利，今晚吃 mian();3534+1
02:01		+1
01:07		-2-3+2
04:26		57%
4/7
==== Member Distribution ==== ^ Solved ^ A ^ B ^ C ^ D ^ E ^ F ^ G ^ H ^ I ^ J ^ | Pantw | | | | | | | | | | √ | | Withinlover | | | | | √ | | | | | | | Gary | √ | | | | | | | | | | (√ for solved, O for upsolved, - for tried but not solved) ---- ====== Solutions ====== ===== A ===== 半天也没搞懂怎么证得，尽量选2，不能选2就选一次3 ===== B ===== ===== C ===== ===== D ===== ===== E ===== 二分然后暴力从后往前推就好了 ===== F ===== ===== G ===== ===== H ===== ===== I ===== ===== J ===== 考虑 DP。对每个结点，考虑其所有儿子的子树，算出它们与对应点的儿子的子树的权值 G[i][j]，算出来之后把它们建成二分图，再直接在二分图上跑一个最小费用最大流即可。 ------------- ====== Comments ====== ptw: * 抢榆枋而止 Gary: * C题思路上有问题，平常都是类似题解的方式讨论，今天脑子抽了 * 在一次提醒自己写板子 Withinlover: * 注 意 肠 道 卫 生 * 现在看E题挺显然的不知道自己当时在懵啥（