05 2012 档案

LCA tarjan 离线算法学习
摘要：最近公共祖先(Least Common Ancestors)LCA定义：对于有根树T的两个结点u、v，最近公共祖先LCA(T,u,v)表示一个结点x，满足x是u、v的祖先且x的深度尽可能大。另一种理解方式是把T理解为一个无向无环图，而LCA(T,u,v)即u到v的最短路上深度最小的点。离线算法Tarjan: 利用并查集优越的时空复杂度，我们可以实现LCA问题的O(n+Q)算法，这里Q表示询问的次数。Tarjan算法基于深度优先搜索的框架，对于新搜索到 的一个结点，首先创建由这个结点构成的集合，再对当前结点的每一个子树进行搜索，每搜索完一棵子树，则可确定子树内的LCA询问都已解决。其他的LCA. 阅读全文
posted @ 2012-05-08 13:48 lmnx 阅读(260) 评论(0) 推荐(0)
hdu Junk-Mail Filter 并查集的合并与删除
摘要：Junk-Mail FilterTime Limit: 15000/8000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 3547Accepted Submission(s): 1079Problem DescriptionRecognizing junk mails is a tough task. The method used here consists of two steps:1) Extract the common characteristics from the in 阅读全文
posted @ 2012-05-03 20:41 lmnx 阅读(893) 评论(0) 推荐(0)
poj Cow Relays 矩阵乘法思想与floyd
摘要：Cow RelaysTime Limit:1000MSMemory Limit:65536KTotal Submissions:3507Accepted:1388DescriptionFor their physical fitness program,N(2 ≤N≤ 1,000,000) cows have decided to run a relay race using theT(2 ≤T≤ 100) cow trails throughout the pasture.Each trail connects two different intersections (1 ≤I1i≤ 1,0 阅读全文
posted @ 2012-05-03 19:30 lmnx 阅读(1027) 评论(0) 推荐(0)
poj Purifying Machine 判定两个二进制串是否相差一位
摘要：Purifying MachineTime Limit : 4000/2000ms (Java/Other) Memory Limit : 131072/65536K (Java/Other)Total Submission(s) : 1 Accepted Submission(s) : 1Problem DescriptionMike is the owner of a cheese factory. He has 2N cheeses and each cheese is given a binary number from 00...0 to 11...1. To keep his ch 阅读全文
posted @ 2012-05-02 21:49 lmnx 阅读(346) 评论(0) 推荐(0)
hdu 无题II 二分+枚举+最大匹配
摘要：无题II Time Limit : 2000/2000ms (Java/Other) Memory Limit : 32768/32768K (Java/Other) Total Submission(s) : 11 Accepted Submission(s) : 7 Problem Description 这是一个简单的游戏，在一个n*n的矩阵中，找n个数使得这n个数都在不同的行和列... 阅读全文
posted @ 2012-05-01 21:28 lmnx 阅读(215) 评论(0) 推荐(0)
hdu Jamie's Contact Groups 二分+二分图多重匹配
摘要：Jamie's Contact Groups Time Limit: 15000/7000 MS (Java/Others) Memory Limit: 65535/65535 K (Java/Others) Total Submission(s): 171 Accepted Submission(s): 46 Problem Description Jamie ... 阅读全文
posted @ 2012-05-01 18:46 lmnx 阅读(231) 评论(0) 推荐(0)
hdu Swap
摘要：SwapTime Limit : 2000/1000ms (Java/Other)Memory Limit : 32768/32768K (Java/Other)Total Submission(s) : 3Accepted Submission(s) : 2Special JudgeProblem DescriptionGiven an N*N matrix with each entry equal to 0 or 1. You can swap any two rows or any two columns. Can you find a way to make all the diag 阅读全文
posted @ 2012-05-01 15:55 lmnx 阅读(332) 评论(0) 推荐(0)
hdu Strategic Game 二分图最大匹配/树形DP
摘要：Strategic GameTime Limit : 20000/10000ms (Java/Other)Memory Limit : 65536/32768K (Java/Other)Total Submission(s) : 4Accepted Submission(s) : 3Problem DescriptionBob enjoys playing computer games, especially strategic games, but sometimes he cannot find the solution fast enough and then he is very sa 阅读全文
posted @ 2012-05-01 13:22 lmnx 阅读(348) 评论(0) 推荐(0)
hdu Rain on your Parade 二分图最大匹配
摘要：Rain on your ParadeTime Limit : 6000/3000ms (Java/Other)Memory Limit : 655350/165535K (Java/Other)Total Submission(s) : 3Accepted Submission(s) : 2Problem DescriptionYou’re giving a party in the garden of your villa by the sea. The party is a huge success, and everyone is here. It’s a warm, sunny ev 阅读全文
posted @ 2012-05-01 12:30 lmnx 阅读(187) 评论(0) 推荐(0)
hdu Arbiter 二分图的另一种用途
摘要：ArbiterTime Limit : 1000/1000ms (Java/Other)Memory Limit : 131072/131072K (Java/Other)Total Submission(s) : 2Accepted Submission(s) : 2Problem DescriptionArbiter is a kind of starship in the StarCraft science-fiction series. The Arbiter-class starship is a Protoss warship specializing in providing p 阅读全文
posted @ 2012-05-01 11:31 lmnx 阅读(297) 评论(0) 推荐(0)
hdu Taxi Cab Scheme
摘要：Taxi Cab SchemeTime Limit : 20000/10000ms (Java/Other)Memory Limit : 65536/32768K (Java/Other)Total Submission(s) : 3Accepted Submission(s) : 3Problem DescriptionRunning a taxi station is not all that simple. Apart from the obvious demand for a centralised coordination of the cabs in order to pick u 阅读全文
posted @ 2012-05-01 10:40 lmnx 阅读(402) 评论(0) 推荐(1)
hdu I'm Telling the Truth
摘要：I'm Telling the TruthTime Limit : 2000/1000ms (Java/Other)Memory Limit : 32768/32768K (Java/Other)Total Submission(s) : 2Accepted Submission(s) : 2Problem DescriptionAfter this year’s college-entrance exam, the teacher did a survey in his class on students’ score. There are n students in the cla 阅读全文
posted @ 2012-05-01 10:04 lmnx 阅读(294) 评论(0) 推荐(0)