Problem K. Master of SequenceTherearetwosequencesa1,a2,··· ,an, b1,b2,··· ,bn. LetS(t) =∑n i=1⌊t−bi ai ⌋. Therearemoperationswithin three kinds as following: • 1 x y: change value ax to y. • 2 x y: change value bx to y. • 3 k: ask min{t|k ≤ S(t)} Inp…

Distance on the tree DSM(Data Structure Master) once learned about tree when he was preparing for NOIP(National Olympiad in Informatics in Provinces) in Senior High School. So when in Data Structure Class in College, he is always absent-minded about…

Master of Sequence 时间限制: 10 Sec  内存限制: 128 MB 题目描述 There are two sequences a1,a2,...,an , b1,b2,...,bn . Let . There are m operations within three kinds as following:• 1 x y: change value ax to y.• 2 x y: change value bx to y.• 3 k: ask min{t|k≤S(t)}…

poj 3111 K Best 最大化平均值 二分思想 题目链接: http://poj.org/problem?id=3111 思路: 挑战程序竞赛书上讲的很好,下面的解释也基本来源于此书 设定条件C(x):=可以选择使得单位重量的价值不小于x 如何判定C(x)是否可行 假设选了某个物品的集合是S,那么单位重量的价值是:\[ \sum\limits_{i \in S} {v_i } /\sum\limits_{i \in S} {w_i } \] 因此就变成了判断是否存在S满足下面的条件:\[…

Problem K. UTF-8 Decoder 题目连接: http://opentrains.snarknews.info/~ejudge/team.cgi?SID=c75360ed7f2c7022&all_runs=1&action=140 Description UTF-8 is a character encoding capable of encoding all possible characters, or code points, in Unicode. Nowadays…

Problem K. Kitchen Robot Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100610 Description Robots are becoming more and more popular. They are used nowadays not only in manufacturing plants, but also at home. One programmer wit…

接下来就要说下无监督机器学习方法,所谓无监督机器学习前面也说过,就是没有标签的情况,对样本数据进行聚类分析.关联性分析等.主要包括K均值聚类(K-means clustering)和关联分析,这两大类都可以说的很简单也可以说的很复杂,学术的东西本身就一直在更新着.比如K均值聚类可以扩展一下形成层次聚类(Hierarchical Clustering),也可以进入概率分布的空间进行聚类,就像前段时间很火的LDA聚类,虽然最近深度玻尔兹曼机(DBM)打败了它,但它也是自然语言处理领域(NLP:Nat…

题目链接:https://codeforces.com/contest/1089/problem/K time limit per test: 2 seconds memory limit per test: 512 megabytes King Kog got annoyed of the usual laxity of his knights — they can break into his hall without prior notice! Thus, the King decided…

题目链接:http://codeforces.com/gym/101981/problem/K Your friend has made a computer video game called “Kangaroo Puzzle” and wants you to give it a try for him. As the name of this game indicates, there are some (at least 2) kangaroos stranded in a puzzle…

Problem K. KMC Attacks 题目连接: http://codeforces.com/gym/100714 Description Warrant VI is a remote planet located in the Koprulu Sector. Warrant VI features a strange huge field, which was discovered by the Kel-Morian Combine (KMC). The KMC is involved…