lypbendlf - 博客园

2018年11月17日

摘要： Given an integer with no more than 9 digits, you are supposed to read it in the traditional Chinese way. Output Fu first if it is negative. For exampl 阅读全文

posted @ 2018-11-17 15:53 lypbendlf 阅读(127) 评论(0) 推荐(0) 编辑

PAT 1135 Is It A Red-Black Tree[难]

摘要： There is a kind of balanced binary search tree named red-black tree in the data structure. It has the following 5 properties: (1) Every node is either 阅读全文

posted @ 2018-11-17 11:05 lypbendlf 阅读(263) 评论(0) 推荐(0) 编辑

PAT 1127 ZigZagging on a Tree[难]

摘要： Suppose that all the keys in a binary tree are distinct positive integers. A unique binary tree can be determined by a given pair of postorder and ino 阅读全文

posted @ 2018-11-17 09:33 lypbendlf 阅读(431) 评论(0) 推荐(0) 编辑

2018年11月16日

线代之计算特征值与特征向量

摘要： > c [,1] [,2] [,3] [,4] [1,] 1 4 7 10 [2,] 2 5 8 11 [3,] 3 6 9 12 > eigen(c) eigen() decomposition $`values` [1] 3.620937e+01 -2.209373e+00 1.599839e-15 ... 阅读全文

posted @ 2018-11-16 10:57 lypbendlf 阅读(445) 评论(0) 推荐(0) 编辑

2018年11月15日

PAT 1117 Eddington Number [难]

摘要： British astronomer Eddington liked to ride a bike. It is said that in order to show off his skill, he has even defined an "Eddington number", E -- tha 阅读全文

posted @ 2018-11-15 16:58 lypbendlf 阅读(179) 评论(0) 推荐(0) 编辑

PAT 1062 Talent and Virtue[难]

摘要： About 900 years ago, a Chinese philosopher Sima Guang wrote a history book in which he talked about people's talent and virtue. According to his theor 阅读全文

posted @ 2018-11-15 16:12 lypbendlf 阅读(157) 评论(0) 推荐(0) 编辑

PAT 1048 Find Coins[比较]

摘要： Eva loves to collect coins from all over the universe, including some other planets like Mars. One day she visited a universal shopping mall which cou 阅读全文

posted @ 2018-11-15 13:47 lypbendlf 阅读(136) 评论(0) 推荐(0) 编辑

协方差矩阵学习[转载]

摘要：转自:https://www.cnblogs.com/terencezhou/p/6235974.html https://www.cnblogs.com/nsnow/p/4758202.html 这个讲到了协方差矩阵的几何解释，，我现在是看不懂的。。。 2020-9-14更新—————— http 阅读全文

posted @ 2018-11-15 13:20 lypbendlf 阅读(314) 评论(0) 推荐(0) 编辑

2018年11月14日

PAT 1140 Look-and-say Sequence [比较]

摘要： Look-and-say sequence is a sequence of integers as the following: D, D1, D111, D113, D11231, D112213111, ... where D is in [0, 9] except 1. The (n+1)s 阅读全文

posted @ 2018-11-14 18:41 lypbendlf 阅读(244) 评论(0) 推荐(0) 编辑

PAT 1089 Insert or Merge[难]

摘要： 1089 Insert or Merge （25 分） According to Wikipedia: Insertion sort iterates, consuming one input element each repetition, and growing a sorted output 阅读全文

posted @ 2018-11-14 17:48 lypbendlf 阅读(118) 评论(0) 推荐(0) 编辑

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