小爷 - 博客园

2016年2月24日

1097. Deduplication on a Linked List (25)

摘要： Given a singly linked list L with integer keys, you are supposed to remove the nodes with duplicated absolute values of the keys. That is, for each va 阅读全文

posted @ 2016-02-24 18:53 小爷阅读(838) 评论(0) 推荐(0) 编辑

1096. Consecutive Factors (20)

摘要： Among all the factors of a positive integer N, there may exist several consecutive numbers. For example, 630 can be factored as 3*5*6*7, where 5, 6, a 阅读全文

posted @ 2016-02-24 18:52 小爷阅读(161) 评论(0) 推荐(0) 编辑

机器学习实战——决策树

摘要： 1、信息熵一些概念 p(x):分类结果x的概率，即分类结果为x的数据量/总数据量信息：l(x) = -log2(p(x))信息熵：信息的期望值 -(p(x1)l(x1) + p(x2)l(x2) + ……) 计算信息熵 1 def calcShannonEnt(dataset): 2 numEnt 阅读全文

posted @ 2016-02-24 01:12 小爷阅读(419) 评论(0) 推荐(0) 编辑

2016年2月23日

1095. Cars on Campus (30)

摘要： Zhejiang University has 6 campuses and a lot of gates. From each gate we can collect the in/out times and the plate numbers of the cars crossing the g 阅读全文

posted @ 2016-02-23 18:54 小爷阅读(628) 评论(0) 推荐(0) 编辑

1094. The Largest Generation (25)

摘要： A family hierarchy is usually presented by a pedigree tree where all the nodes on the same level belong to the same generation. Your task is to find t 阅读全文

posted @ 2016-02-23 18:50 小爷阅读(281) 评论(0) 推荐(0) 编辑

1093. Count PAT's (25)

摘要： The string APPAPT contains two PAT's as substrings. The first one is formed by the 2nd, the 4th, and the 6th characters, and the second one is formed 阅读全文

posted @ 2016-02-23 18:48 小爷阅读(517) 评论(0) 推荐(0) 编辑

1092. To Buy or Not to Buy (20)

摘要： Eva would like to make a string of beads with her favorite colors so she went to a small shop to buy some beads. There were many colorful strings of b 阅读全文

posted @ 2016-02-23 18:46 小爷阅读(294) 评论(0) 推荐(0) 编辑

2016年2月22日

机器学习实战——k-邻近算法：约会网站

摘要： 1、kNN 算法算法说明： set<X1,X2……Xn> 为已知类别数据集，预测点Xt 的类别：（1）计算中的set中每一个点与Xt的距离（2）按距离增序排列（3）选择距离最小的前k个点（4）确定前k个点所在的类别的出现频率（5）返回频率最高的类别作为测试的结果 1 from nump 阅读全文

posted @ 2016-02-22 20:18 小爷阅读(2823) 评论(0) 推荐(0) 编辑

2016年2月14日

1057. Stack (30)

摘要： Stack is one of the most fundamental data structures, which is based on the principle of Last In First Out (LIFO). The basic operations include Push ( 阅读全文

posted @ 2016-02-14 01:13 小爷阅读(266) 评论(0) 推荐(0) 编辑

2016年2月2日

1017. Queueing at Bank (25)

摘要： Suppose a bank has K windows open for service. There is a yellow line in front of the windows which devides the waiting area into two parts. All the c 阅读全文

posted @ 2016-02-02 21:14 小爷阅读(194) 评论(0) 推荐(0) 编辑

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