Difference between revisions of "Training 2: Probability and Expectation"

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Solved by Kilo_5723 && Weaver_zhu.
 
Solved by Kilo_5723 && Weaver_zhu.
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题意:给定一个无向联通图,每一条边有一个权值,从起点开始每次随机选一条边走,问走到终点时,走过的所有边权值异或和的期望值。
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题解:对于边权的每一个二进制位分别求解,将每个点到终点路径异或和的期望值设为未知数,对每一个点及其所有出边列出方程,高斯消元求解即可。
  
 
== Problem B ==
 
== Problem B ==

Revision as of 14:43, 8 May 2019

Problem A

Solved by Kilo_5723 && Weaver_zhu.

题意:给定一个无向联通图,每一条边有一个权值,从起点开始每次随机选一条边走,问走到终点时,走过的所有边权值异或和的期望值。

题解:对于边权的每一个二进制位分别求解,将每个点到终点路径异或和的期望值设为未知数,对每一个点及其所有出边列出方程,高斯消元求解即可。

Problem B

Solved by Kilo_5723 && Weaver_zhu.

Problem C

Solved by Kilo_5723.

Problem D

Solved by Kilo_5723.

Problem E

Solved by Kilo_5723.

Problem F

Solved by Kilo_5723.

Problem G

Solved by Kilo_5723.

Problem H

Solved by Kilo_5723.