摘要： Hou Yi's secretTime Limit: 2000/1000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 877Accepted Submission(s): 285Problem DescriptionLong long ago, in the time of Chinese emperor Yao, ten suns rose into the sky. They burned the crops and scorched the bushes and tre 阅读全文

摘要： One Person GameTime Limit: 1 Second Memory Limit: 32768 KB Special JudgeThere is a very simple and interesting one-person game. You have 3 dice, namely Die1, Die2 and Die3. Die1 has K1 faces. Die2 has K2 faces. Die3 has K3 faces. All the dice are fair dice, so the probability of rolling each value.. 阅读全文

摘要： Collecting BugsTime Limit: 10000MSMemory Limit: 64000KTotal Submissions: 1244Accepted: 523Case Time Limit: 2000MSSpecial JudgeDescriptionIvan is fond of collecting. Unlike other people who collect post stamps, coins or other material stuff, he collects software bugs. When Ivan gets a new program, he 阅读全文

摘要： 概率DP主要用于求解期望、概率等题目。转移方程有时候比较灵活。一般求概率是正推，求期望是逆推。通过题目可以体会到这点。首先先推荐几篇参考的论文：《信息学竞赛中概率问题求解初探》《浅析竞赛中一类数学期望问题的解决方法》 《有关概率和期望问题的研究 》1、POJ 3744 Scout YYF I此题是一个用矩阵优化的求概率的题目。主要思想是分段，根据转移方程用矩阵求解。题解见 herePOJ 3744/*POJ 3744C++ 0ms 184K*/#include<stdio.h>#include<string.h>#include<algorithm>#inc 阅读全文

摘要： Scout YYF ITime Limit: 1000MSMemory Limit: 65536KTotal Submissions: 3723Accepted: 928DescriptionYYF is a couragous scout. Now he is on a dangerous mission which is to penetrate into the enemy's base. After overcoming a series difficulties, YYF is now at the start of enemy's famous "mine 阅读全文

摘要： 这几天学习了一下插头DP，刷了11道题。对插头DP有了点理解。插头DP就先告一段落吧！ 后面还有插头DP的广义路径和其它复杂应用，以后有机会再补上吧！ kuangbin首先入门推荐的还是cdq的论文：《基于连通性状态压缩的动态规划问题》http://wenku.baidu.com/view/4fe4ac659b6648d7c1c74633.html上面的论文关于插头和轮廓线等概念讲得很清楚。而且关于插头DP的精髓也讲得很透了。插头DP其实就是每格进行状态转移。看懂原理和写代码还是有段距离的，可以结合代码去加深理解原理。同时形成适合自己风格的代码模板。HDU 1693 Eat the Trees 阅读全文

摘要： circuitsTime Limit: 30000/15000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 418Accepted Submission(s): 141Problem Description Given a map of N * M (2 <= N, M <= 12) , '.' means empty, '*' means walls. You need to build K circuits and no circuit 阅读全文

摘要： Beautiful MeadowTime Limit: 5 Seconds Memory Limit: 32768 KBTom's MeadowTom has a meadow in his garden. He divides it into N * M squares. Initially all the squares are covered with grass and there may be some squares cannot be mowed.(Let's call them forbidden squares.) He wants to mow down t 阅读全文

摘要： Problem 1977 Pandora adventureAccept: 246Submit: 816Time Limit: 1000 mSecMemory Limit : 32768 KB Problem DescriptionThe pollution of the earth is so serious that people can not survive any more. Fortunately, people have found a new planet that maybe has life, and we call it "Pandora Planet" 阅读全文

摘要： Eat the TreesTime Limit: 4000/2000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1663Accepted Submission(s): 783Problem DescriptionMost of us know that in the game called DotA(Defense of the Ancient), Pudge is a strong hero in the first period of the game. When the ga 阅读全文