来翻译一下官方文档,但是建议看英文原文,本文可能会出现一些错误,虽然不是为了方便自己查阅用的. 首先,对于人 \(i\),定义 \(r_i\) 是他的 rating,对于人 \(i,j\),定义 \(P_{i,j}\) 为在一场比赛中 \(i\) 比 \(j\) 强的概率. Codeforces 想尽力让这个柿子成立: \[P_{i,j}=\frac{1}{1+10^{\frac{r_j-r_i}{400}}}\] 一场比赛开始前,定义 \(seed_i\) 为第 \(i\) 个人的期望排名.明…

1. Elo Rating System Elo Rating System对于很多人来说比较陌生,根据wikipedia上的解释:Elo评分系统是一种用于计算对抗比赛(例如象棋对弈)中对手双方技能水平的方法,它由Arpad Elo创建.(The Elo rating system is a method for calculating the relative skill levels of players in competitor-versus-competitor games such…

package org.cc.foo_008; import java.util.ArrayList; import java.util.List; import java.util.Random; public class Main_006 { public static void main(String[] args) { EloRatingSystemDemo e=new EloRatingSystemDemo(); e.show(); // User u=e.gamer.get(new…

转载请注明出处: http://www.cnblogs.com/fraud/          ——by fraud System Administrator Bob got a job as a system administrator in X corporation. His first task was to connect n servers with the help of m two-way direct connection so that it becomes possible…

 Registration system A new e-mail service "Berlandesk" is going to be opened in Berland in the near future. The site administration wants to launch their project as soon as possible, that's why they ask you to help. You're suggested to implement…

来翻译一下官方文档,但是建议看英文原文,本文可能会出现一些错误,只是为了方便自己查阅用的. 对于你的每一场rated比赛,会有一个Performance值\(X_i\),你的rating是\(X_i-f(i)\)的加权平均,其中\(f(1)=1200\)而\(f(i)\)单调递减.也就是说,如果你的Performance值稳定在\(X\)上,你的Rating会从\(X-1200\)逐渐上升为\(X\). 那如何计算Performance呢?对于每个选手,有一个值叫做\(APerf\)(Avera…

把v和2结点交换, 1和v连,其它点和v之间能够互相连. #include <iostream> #include <cstdlib> #include <cstring> #include <string> #include <cstdio> #include <cmath> #include <algorithm> using namespace std; int n,m,v,flag,i,cnt,j; int mai…

A.B 两个待比较.评价的对象,分别打分为 RA,RB,则各自获胜的期望值为: ⎧⎩⎨⎪⎪⎪⎪⎪⎪EA=11+10(RB−RA)/400.EB=11+10(RA−RB)/400. 不妨令 QA=10RA/400,QB=10RB/400,则有: ⎧⎩⎨⎪⎪⎪⎪⎪⎪EA=QAQA+QB.EB=QBQA+QB. 1. 基本推论 EA+EB=1 EAEB=QAQB 2. K-factor R′A=RA+K(SA−EA) EA 某次比赛的期望得分: SA 该次比赛的实际得分: K K=16 对于专业运动员…

A. Is it rated? time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output Is it rated? Here it is. The Ultimate Question of Competitive Programming, Codeforces, and Everything. And you are here to a…

A. Is it rated? 题面 Is it rated? Here it is. The Ultimate Question of Competitive Programming, Codeforces, and Everything. And you are here to answer it. Another Codeforces round has been conducted. No two participants have the same number of points.…