地址

O: 当场通过

?: 赛后通过

.: 尚未通过

A Secret of Chocolate Poles

solved by chelly

chelly‘s solution

B Parallel Lines

solved by ch

ch‘s solution

C Medical Checkup

solved by chelly

chelly‘s solution

D Digital Clock

unsolved

E Black or White

solved by chelly&ch

chelly‘s solution

F Pizza Delivery

solved by chelly&ch

chelly‘s solution

G Rendezvous on a Tetrahedron

upsolved by feynman

feynman‘s solution

H Homework

unsolved

I Starting a Scenic Railroad Service

solved by chelly

chelly‘s solution

J String Puzzle

unsolved

K Counting Cycles

upsolved by chelly

chelly‘s solution

先求出一棵生成树，那么非树边顶多16条，二进制枚举所有的组合，算经过某几条非树边是否存在一个环（如果存在则一定是唯一的）
对于如何判断，只需要将一个非树边对应的树上的链全部异或一下，那么对于这组选择，选出边权为1的边组成一个图，判断这个图是不是一个简单环即可
注意原树会很大，\(2^16\)次遍历原树是会TLE，我们只需要在虚树上做即可

Dirt Replay

F -1 双连通分量的板子抄错了

E -3 一发是dp式子写错了，还有两发是因为单调队列优化时候的单调队列方向写反了

2017-2018 ACM-ICPC, Asia Tsukuba Regional Contest

原文：https://www.cnblogs.com/Amadeus/p/10115436.html