2015 年 6月随笔档案 - 世界到处都是小星星

数据处理问题

摘要：key points:1 conversion between different types2 overflow 会有比较多corner cases需要考虑3 iterationrelated questions:Median of Two Sorted ArraysReverse Integer... 阅读全文

posted @ 2015-06-23 01:21 世界到处都是小星星阅读(126) 评论(0) 推荐(0) 编辑

天题系列： Shortest Palindrome

摘要：今天完整刷完leetcode除了自己看不懂follow不下来的 199道题。。。纪念一下Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find ... 阅读全文

posted @ 2015-06-18 03:33 世界到处都是小星星阅读(281) 评论(0) 推荐(0) 编辑

天题系列： Read N Characters Given Read4

摘要：ref http://blog.csdn.net/u013325815/article/details/41892135The API:int read4(char *buf)reads 4 characters at a time from a file.The return value is t... 阅读全文

posted @ 2015-06-17 11:49 世界到处都是小星星阅读(254) 评论(0) 推荐(0) 编辑

天题系列： Best Time to Buy and Sell Stock IV

摘要：Say you have an array for which theithelement is the price of a given stock on dayi.Design an algorithm to find the maximum profit. You may complete a... 阅读全文

posted @ 2015-06-17 10:01 世界到处都是小星星阅读(177) 评论(0) 推荐(0) 编辑

Reverse Words in a String II

摘要：Given an input string, reverse the string word by word. A word is defined as a sequence of non-space characters.The input string does not contain lead... 阅读全文

posted @ 2015-06-17 06:23 世界到处都是小星星阅读(167) 评论(0) 推荐(0) 编辑

Largest Number

摘要：Given a list of non negative integers, arrange them such that they form the largest number.For example, given[3, 30, 34, 5, 9], the largest formed num... 阅读全文

posted @ 2015-06-17 06:08 世界到处都是小星星阅读(159) 评论(0) 推荐(0) 编辑

天题系列： Dungeon Game

摘要：The demons had captured the princess (P) and imprisoned her in the bottom-right corner of a dungeon. The dungeon consists of M x N rooms laid out in a... 阅读全文

posted @ 2015-06-17 05:36 世界到处都是小星星阅读(333) 评论(0) 推荐(0) 编辑

Binary Search Tree Iterator

摘要：完全没有想法实际上是in order traversal而已public class BSTIterator { public TreeNode crt; public Stack st = new Stack(); public BSTIterator(TreeNode ... 阅读全文

posted @ 2015-06-17 05:05 世界到处都是小星星阅读(96) 评论(0) 推荐(0) 编辑

天题系列： LRU Cache

摘要：Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations:getandset.get(key)- Get the valu... 阅读全文

posted @ 2015-06-17 03:38 世界到处都是小星星阅读(181) 评论(0) 推荐(0) 编辑

Factorial Trailing Zeroes

摘要：Given an integern, return the number of trailing zeroes inn!.ref 抄自达达http://www.danielbit.com/blog/puzzle/leetcode/leetcode-factorial-trailing-zeroes首... 阅读全文

posted @ 2015-06-16 05:51 世界到处都是小星星阅读(129) 评论(0) 推荐(0) 编辑

Excel Sheet Column Number

摘要：Related to questionExcel Sheet Column TitleGiven a column title as appear in an Excel sheet, return its corresponding column number.For example: A ... 阅读全文

posted @ 2015-06-16 05:41 世界到处都是小星星阅读(170) 评论(0) 推荐(0) 编辑

Excel Sheet Column Title

摘要：Given a positive integer, return its corresponding column title as appear in an Excel sheet.For example: 1 -> A 2 -> B 3 -> C ... 26 ->... 阅读全文

posted @ 2015-06-16 05:37 世界到处都是小星星阅读(155) 评论(0) 推荐(0) 编辑

Compare Version Numbers

摘要：Compare two version numbersversion1andversion2.Ifversion1>version2return 1, ifversion1v2) return 1; if(v1<v2) return -1; ... 阅读全文

posted @ 2015-06-16 05:29 世界到处都是小星星阅读(184) 评论(0) 推荐(0) 编辑

天题系列： Maximum Gap --bucket sort

摘要：Given an unsorted array, find the maximum difference between the successive elements in its sorted form.Try to solve it in linear time/space.Return 0 ... 阅读全文

posted @ 2015-06-16 05:13 世界到处都是小星星阅读(253) 评论(0) 推荐(0) 编辑

One Edit Distance

摘要：Given two strings S and T, determine if they are both one edit distance apart.Hint:1. If | n – m | is greater than 1, we know immediately both are not... 阅读全文

posted @ 2015-06-16 04:16 世界到处都是小星星阅读(224) 评论(0) 推荐(0) 编辑

Binary Tree Upside Down

摘要：网上抄的http://blog.csdn.net/whuwangyi/article/details/43186045Given a binary tree where all the right nodes are either leaf nodes with a sibling (a left ... 阅读全文

posted @ 2015-06-16 03:27 世界到处都是小星星阅读(174) 评论(0) 推荐(0) 编辑

Min Stack

摘要：Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.push(x) -- Push element x onto stack.pop() -- Removes... 阅读全文

posted @ 2015-06-16 03:03 世界到处都是小星星阅读(112) 评论(0) 推荐(0) 编辑

Reverse Words in a String

摘要：话说我们昨晚去看了侏罗纪公园，原来xd就是我最爱的巨幕，来美国这么多年了，怀念和小星星一路成长，一路看电影的经历，avatar是我们在美国一起看的第一部电影。老美看完好片子，还喜欢鼓个掌。这题one pass in place就是麻烦，要多做个string来判断单词要用到sb的insert，不过可以... 阅读全文

posted @ 2015-06-16 01:06 世界到处都是小星星阅读(157) 评论(0) 推荐(0) 编辑

Evaluate Reverse Polish Notation

摘要：很简单的stack，注意operation orderpublic class Solution { public int evalRPN(String[] tokens) { if(tokens ==null|| tokens.length==0) return 0; ... 阅读全文

posted @ 2015-06-15 04:39 世界到处都是小星星阅读(133) 评论(0) 推荐(0) 编辑

Binary Tree Postorder Traversal

摘要：http://bookshadow.com/weblog/2015/01/19/leetcode-binary-tree-postorder-traversal/http://bookshadow.com/weblog/2015/01/19/binary-tree-post-order-traver... 阅读全文

posted @ 2015-06-13 11:44 世界到处都是小星星阅读(102) 评论(0) 推荐(0) 编辑

树的总结=转载

摘要：ref linkhttp://blog.sina.com.cn/s/blog_eb52001d0102v1si.html摘抄感谢以下文章的作者：BIN大神的大总结：http://blog.csdn.net/fightforyourdream/article/details/16843303 面试... 阅读全文

posted @ 2015-06-13 10:11 世界到处都是小星星阅读(179) 评论(0) 推荐(0) 编辑

Binary Tree Preorder Traversal

摘要：树的遍历当初觉得难死，现在还好public class Solution { public ArrayList preorderTraversal(TreeNode root) { ArrayList res = new ArrayList(); if(root=... 阅读全文

posted @ 2015-06-13 07:00 世界到处都是小星星阅读(109) 评论(0) 推荐(0) 编辑

Contains Duplicate III

摘要：Given an array of integers, find out whether there are two distinct indicesiandjin the array such that the difference betweennums[i]andnums[j]is at mo... 阅读全文

posted @ 2015-06-13 00:48 世界到处都是小星星阅读(1616) 评论(0) 推荐(0) 编辑

Invert Binary Tree

摘要：Invert a binary tree. 4 / \ 2 7 / \ / \1 3 6 9to 4 / \ 7 2 / \ / \9 6 3 1Trivia:This problem was inspired bythis... 阅读全文

posted @ 2015-06-12 23:50 世界到处都是小星星阅读(271) 评论(0) 推荐(0) 编辑

Implement Stack using Queues

摘要：还有2个queue做，没写class MyStack { public Queue q = new LinkedList(); //cc150的问题，好像 // single queue public void push(int x) { q.add((int)... 阅读全文

posted @ 2015-06-12 09:50 世界到处都是小星星阅读(116) 评论(0) 推荐(0) 编辑

Word Break I,II

摘要：Given a stringsand a dictionary of wordsdict, determine ifscan be segmented into a space-separated sequence of one or more dictionary words.For exampl... 阅读全文

posted @ 2015-06-12 08:44 世界到处都是小星星阅读(170) 评论(0) 推荐(0) 编辑

天题系列： Candy

摘要：排排坐分果果，这道题还是蛮难想的，答案忘了从哪里看的了 public int candy(int[] ratings) { if(ratings == null) return 0; int len = ratings.length; int res ... 阅读全文

posted @ 2015-06-12 06:45 世界到处都是小星星阅读(165) 评论(0) 推荐(0) 编辑

Gas Station

摘要：我觉得这道题是dp比较有趣的应用吧，但是老用不熟sigh一下public class Solution { public int canCompleteCircuit(int[] gas, int[] cost) { int total=0, curRem=0, curSum=0... 阅读全文

posted @ 2015-06-12 05:57 世界到处都是小星星阅读(143) 评论(0) 推荐(0) 编辑

Clone Graph

摘要：典型的dfs，做个hashmap判断是否存过（oldnode，newnode）最后怎么把neighbor加入到hm对应node的neighbor list中比较关键public class Solution { public UndirectedGraphNode cloneGraph(Und... 阅读全文

posted @ 2015-06-12 04:34 世界到处都是小星星阅读(125) 评论(0) 推荐(0) 编辑

天题系列： Palindrome Partitioning II

摘要：Given a strings, partitionssuch that every substring of the partition is a palindrome.Return the minimum cuts needed for a palindrome partitioning ofs... 阅读全文

posted @ 2015-06-11 13:25 世界到处都是小星星阅读(133) 评论(0) 推荐(0) 编辑

Palindrome Partitioning

摘要：正常dfspublic class Solution { public ArrayList> partition(String s) { ArrayList> res = new ArrayList>(); if(s==null||s.length()==0) re... 阅读全文

posted @ 2015-06-11 11:30 世界到处都是小星星阅读(135) 评论(0) 推荐(0) 编辑

Surrounded Regions 感染列岛

摘要：Given a 2D board containing'X'and'O', capture all regions surrounded by'X'.A region is captured by flipping all'O's into'X's in that surrounded region... 阅读全文

posted @ 2015-06-11 06:29 世界到处都是小星星阅读(269) 评论(0) 推荐(0) 编辑

Sum Root to Leaf Numbers

摘要：Given a binary tree containing digits from0-9only, each root-to-leaf path could represent a number.An example is the root-to-leaf path1->2->3which rep... 阅读全文

posted @ 2015-06-11 04:03 世界到处都是小星星阅读(154) 评论(0) 推荐(0) 编辑

天题系列：Word Ladder II

摘要：乍一看还真以为和1 一样，呵呵当然不是啦Given two words (startandend), and a dictionary, find all shortest transformation sequence(s) fromstarttoend, such that:Only one l... 阅读全文

posted @ 2015-06-11 03:00 世界到处都是小星星阅读(115) 评论(0) 推荐(0) 编辑

Word Ladder---BFS

摘要：还是参考爱做饭同学http://www.cnblogs.com/springfor/p/3893499.htmlGiven two words (beginWordandendWord), and a dictionary, find the length of shortest transform... 阅读全文

posted @ 2015-06-11 00:55 世界到处都是小星星阅读(293) 评论(0) 推荐(0) 编辑

Valid Palindrome

摘要：基础但是要掌握 int a = 'A'这种写法,以及s.trim(); s = s.toUpperCase();public class Solution { public boolean isPalindrome(String s) { if(s==null ||... 阅读全文

posted @ 2015-06-10 11:04 世界到处都是小星星阅读(154) 评论(0) 推荐(0) 编辑

Binary Tree Maximum Path Sum

摘要：Given a binary tree, find the maximum path sum.The path may start and end at any node in the tree.For example:Given the below binary tree, 1 ... 阅读全文

posted @ 2015-06-10 10:48 世界到处都是小星星阅读(130) 评论(0) 推荐(0) 编辑

Populating Next Right Pointers in Each Node I or II

摘要：Follow up for problem "Populating Next Right Pointers in Each Node".What if the given tree could be any binary tree? Would your previous solution stil... 阅读全文

posted @ 2015-06-10 10:34 世界到处都是小星星阅读(117) 评论(0) 推荐(0) 编辑

天题系列： Distinct Subsequences

摘要：Given a stringSand a stringT, count the number of distinct subsequences ofTinS.A subsequence of a string is a new string which is formed from the orig... 阅读全文

posted @ 2015-06-10 07:26 世界到处都是小星星阅读(141) 评论(0) 推荐(0) 编辑

Flatten Binary Tree to Linked List

摘要：Given a binary tree, flatten it to a linked list in-place.For example,Given 1 / \ 2 5 / \ \ 3 4 6The flattened t... 阅读全文

posted @ 2015-06-10 06:35 世界到处都是小星星阅读(148) 评论(0) 推荐(0) 编辑

Minimum Depth of Binary Tree

摘要：就recursive做，简单题public class Solution { public int minDepth(TreeNode root) { if(root==null) return 0; if (root.left==null && root.righ... 阅读全文

posted @ 2015-06-10 06:14 世界到处都是小星星阅读(151) 评论(0) 推荐(0) 编辑

Path Sum I, II

摘要：简单题IGiven a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given su... 阅读全文

posted @ 2015-06-10 06:02 世界到处都是小星星阅读(208) 评论(0) 推荐(0) 编辑

Balanced Binary Tree

摘要：超简洁的代码本来考虑是不是真的要每个点求一个maxDepth，看来是的哟public class Solution { public boolean isBalanced(TreeNode root) { if (root==null) return true; i... 阅读全文

posted @ 2015-06-10 05:38 世界到处都是小星星阅读(120) 评论(0) 推荐(0) 编辑

Convert Sorted Array to Binary Search Tree

摘要：Given an array where elements are sorted in ascending order, convert it to a height balanced BST.题解完全抄自ref的说明，感谢！“题解：先复习下什么是二叉搜索树（引自Wikipedia）：二叉查找树（B... 阅读全文

posted @ 2015-06-10 05:08 世界到处都是小星星阅读(201) 评论(0) 推荐(0) 编辑

Maximum Depth of Binary Tree

摘要：Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest le... 阅读全文

posted @ 2015-06-10 04:56 世界到处都是小星星阅读(148) 评论(0) 推荐(0) 编辑

Binary Tree Zigzag Level Order Traversal

摘要：跟之前的解法一模一样Binary Tree Level Order Traversal I,II 不赘述public class Solution { public ArrayList> zigzagLevelOrder(TreeNode root) { ArrayList> r... 阅读全文

posted @ 2015-06-10 04:43 世界到处都是小星星阅读(137) 评论(0) 推荐(0) 编辑

Binary Tree Level Order Traversal I,II

摘要：Given a binary tree, return thelevel ordertraversal of its nodes' values. (ie, from left to right, level by level).For example:Given binary tree{3,9,2... 阅读全文

posted @ 2015-06-10 04:27 世界到处都是小星星阅读(426) 评论(0) 推荐(0) 编辑

Symmetric Tree

摘要：有个问题，就是不能和same tree一样光看root 做recursive而是必须比较左右节点，因为对称是指整个树否则就会出现 1 2 2 # 3 3public class Solution { public boolean isSymmetric(TreeNode root) { ... 阅读全文

posted @ 2015-06-10 03:16 世界到处都是小星星阅读(115) 评论(0) 推荐(0) 编辑

Same Tree

摘要：简单题ref“使用的是先序遍历，算法的复杂度跟遍历是一致的，如果使用递归，时间复杂度是O(n)，空间复杂度是O(logn)。” by codegankerhttp://blog.csdn.net/linhuanmars/article/details/22839819•Time to search ... 阅读全文

posted @ 2015-06-10 03:03 世界到处都是小星星阅读(133) 评论(0) 推荐(0) 编辑

天题系列： Recover Binary Search Tree

摘要：Two elements of a binary search tree (BST) are swapped by mistake.Recover the tree without changing its structure.Note:A solution using O(n) space is ... 阅读全文

posted @ 2015-06-10 02:55 世界到处都是小星星阅读(210) 评论(0) 推荐(0) 编辑

Validate Binary Search Tree

摘要：Given a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtree of a node contains only n... 阅读全文

posted @ 2015-06-10 00:51 世界到处都是小星星阅读(157) 评论(0) 推荐(0) 编辑

Interleaving String

摘要：Givens1,s2,s3, find whethers3is formed by the interleaving ofs1ands2.For example,Given:s1="aabcc",s2="dbbca",Whens3="aadbbcbcac", return true.Whens3="... 阅读全文

posted @ 2015-06-10 00:39 世界到处都是小星星阅读(226) 评论(0) 推荐(0) 编辑

Unique Binary Search Trees I, II

摘要：Givenn, how many structurally uniqueBST's(binary search trees) that store values 1...n?For example,Givenn= 3, there are a total of 5 unique BST's. 1... 阅读全文

posted @ 2015-06-09 10:54 世界到处都是小星星阅读(200) 评论(0) 推荐(0) 编辑

Restore IP Addresses

摘要：Given a string containing only digits, restore it by returning all possible valid IP address combinations.For example:Given"25525511135",return["255.2... 阅读全文

posted @ 2015-06-09 10:32 世界到处都是小星星阅读(312) 评论(0) 推荐(0) 编辑

Decode Ways

摘要：message containing letters fromA-Zis being encoded to numbers using the following mapping:'A' -> 1'B' -> 2...'Z' -> 26Given an encoded message contain... 阅读全文

posted @ 2015-06-09 07:54 世界到处都是小星星阅读(116) 评论(0) 推荐(0) 编辑

天题系列： Scramble String -- 三维动态规划

摘要：题目：Given a strings1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively.Below is one possible representat... 阅读全文

posted @ 2015-06-09 05:51 世界到处都是小星星阅读(585) 评论(0) 推荐(0) 编辑

Count Complete Tree Nodes

摘要：complete tree,except possibly the last, is completely filled, and all nodes in the last level are as far left as possible.from wiki本来在考虑最底层到底满不满，发现是通过... 阅读全文

posted @ 2015-06-09 03:32 世界到处都是小星星阅读(267) 评论(0) 推荐(0) 编辑

Rectangle Area

摘要：来说说看问题急躁，一开始就理所当然的想问的是overlapped area，实际上是total。脑子里一堆边界条件，看了ref觉得很简洁http://blog.csdn.net/foreverling/article/details/46411069public class Solution { ... 阅读全文

posted @ 2015-06-09 01:09 世界到处都是小星星阅读(207) 评论(0) 推荐(0) 编辑

Combinations

摘要：典型的dfs题，建议在其他dfs之前做public class Solution { public ArrayList> combine(int n, int k) { ArrayList> res = new ArrayList>(); if(nn) return... 阅读全文

posted @ 2015-06-06 04:05 世界到处都是小星星阅读(154) 评论(0) 推荐(0) 编辑

Edit Distance

摘要：public class Solution { public int minDistance(String word1, String word2) { if(word1==null||word1.length()==0) return word2.length(); ... 阅读全文

posted @ 2015-06-06 01:14 世界到处都是小星星阅读(108) 评论(0) 推荐(0) 编辑

Simplify Path

摘要：几个corner cases要清楚refhttp://www.cnblogs.com/springfor/p/3869666.html引用一个用法注意“判断字符串相等与否要用.equals()，因为是引用类型。要注意split函数是可以split出空字符的，例如：//b/ 会被split结果为[""... 阅读全文

posted @ 2015-06-05 05:40 世界到处都是小星星阅读(121) 评论(0) 推荐(0) 编辑

Climbing Stairs

摘要：public class Solution { public int climbStairs(int n) { int[] res =new int[n+3]; // 因为如果n<3,至少希望把前三个位置做出来 res[0] = 0; res[1]... 阅读全文

posted @ 2015-06-05 04:10 世界到处都是小星星阅读(121) 评论(0) 推荐(0) 编辑

Maximal Square

摘要：Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area.For example, given the following matr... 阅读全文

posted @ 2015-06-05 03:56 世界到处都是小星星阅读(421) 评论(0) 推荐(0) 编辑

If you had an array of 1 million values and you had to remove duplicates

摘要：http://www.quora.com/Whats-the-best-way-to-delete-duplicates-from-a-sorted-array-in-math-O-log-N-math-time-and-math-O-1-math-spacehttps://mtatar.wordp... 阅读全文

posted @ 2015-06-04 00:47 世界到处都是小星星阅读(151) 评论(0) 推荐(0) 编辑

ipython 学习笔记 2 network graph--NetworkX

摘要：如果NetworkX不好用，pip uninstall 然后install1) 看每个node的social情况In [1]: import networkx as nxIn [2]: nx.read 比如nx.read_adjlist nx.read_dot nx.read_edgelist这个时... 阅读全文

posted @ 2015-06-03 12:27 世界到处都是小星星阅读(503) 评论(0) 推荐(0) 编辑

ipython 学习笔记 1 基础

摘要：ref: Learning Ipython for interactive computing and data visualizationcode website:http://ipython.rossant.net.启动：基础，可以用powershell在window下实现近似linux操作no... 阅读全文

posted @ 2015-06-03 12:03 世界到处都是小星星阅读(486) 评论(0) 推荐(0) 编辑

Sqrt(x)

摘要：看cast type比较重要，public class Solution { public int sqrt(int x) { // 巧妙使用二分法 // ref http://www.cnblogs.com/springfor/p/3857772.html ... 阅读全文

posted @ 2015-06-03 02:07 世界到处都是小星星阅读(140) 评论(0) 推荐(0) 编辑

Valid Number

摘要：还没刷，感觉好复杂，先把看到的做法记录一下http://blog.csdn.net/kenden23/article/details/18696083 阅读全文

posted @ 2015-06-03 01:55 世界到处都是小星星阅读(113) 评论(0) 推荐(0) 编辑

Permutation Sequence

摘要：The set[1,2,3,…,n]contains a total ofn! unique permutations.By listing and labeling all of the permutations in order,We get the following sequence (ie... 阅读全文

posted @ 2015-06-02 09:19 世界到处都是小星星阅读(951) 评论(0) 推荐(0) 编辑

Length of Last Word

摘要：简单题public class Solution { public int lengthOfLastWord(String s) { s = s.trim(); if(s==null||s.length()==0) return 0; int len ... 阅读全文

posted @ 2015-06-02 08:00 世界到处都是小星星阅读(116) 评论(0) 推荐(0) 编辑

Pow(x, n)

摘要：数据处理题目摘抄自爱做饭 http://www.cnblogs.com/springfor/p/3870929.html“题解：pow(x,n)就是求x的n次方。x的N次方可以看做：x^n = x^(n/2)*x^(n/2)*x^(n%2)。所以利用递归求解，当n==1的时候，x^n=x。当然n是可... 阅读全文

posted @ 2015-06-02 07:54 世界到处都是小星星阅读(241) 评论(0) 推荐(0) 编辑

Permutations I & II

摘要：IGiven a collection of numbers, return all possible permutations.For example,[1,2,3]have the following permutations:[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3... 阅读全文

posted @ 2015-06-02 07:44 世界到处都是小星星阅读(165) 评论(0) 推荐(0) 编辑

天题系列： Wildcard Matching

摘要：题解抄自“http://simpleandstupid.com/2014/10/26/wildcard-matching-leetcode-%E8%A7%A3%E9%A2%98%E7%AC%94%E8%AE%B0/”“Implement wildcard pattern matching with ... 阅读全文

posted @ 2015-06-02 06:52 世界到处都是小星星阅读(159) 评论(0) 推荐(0) 编辑

Count and Say

摘要：依然觉得蛮无聊的，注意返回的是第n个（从1开始算起）stringThe count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...1is read off a... 阅读全文

posted @ 2015-06-02 05:34 世界到处都是小星星阅读(163) 评论(0) 推荐(0) 编辑

Longest Valid Parentheses

摘要：这道题最大的问题是位置容易想不清楚public class Solution { public int longestValidParentheses(String s) { // http://blog.csdn.net/linhuanmars/article/details/... 阅读全文

posted @ 2015-06-02 04:58 世界到处都是小星星阅读(118) 评论(0) 推荐(0) 编辑

无聊啊 Next Permutation

摘要：不甚知道意义的题目，不过数组reverse值得复习一下哟public class Solution { public void nextPermutation(int[] num) { //这个题目意义何在啊唉 if (num==null || nu... 阅读全文

posted @ 2015-06-02 04:22 世界到处都是小星星阅读(142) 评论(0) 推荐(0) 编辑

Divide Two Integers

摘要：Divide two integers without using multiplication, division and mod operator.比有趣在于1 提速过程 2怎么判断符号正负public class Solution { public int divide(int divi... 阅读全文

posted @ 2015-06-02 03:32 世界到处都是小星星阅读(129) 评论(0) 推荐(0) 编辑

Boyer-Moore: Implement strStr() --- find a needle in a haystack

摘要：https://www.youtube.com/watch?v=izMKq3epJ-QBoyer-Moore algrt 关于skip的部分很重要Implement strStr().Returns the index of the first occurrence of needle in hay... 阅读全文

posted @ 2015-06-02 02:59 世界到处都是小星星阅读(262) 评论(0) 推荐(0) 编辑

Generate Parentheses

摘要：dfs 的一个关键是termination conditionpublic class Solution { public ArrayList generateParenthesis(int n) { ArrayList res = new ArrayList(); ... 阅读全文

posted @ 2015-06-02 00:08 世界到处都是小星星阅读(107) 评论(0) 推荐(0) 编辑

scikit learning tutorial

摘要：http://blog.kaggle.com/author/kevin-markham/ 阅读全文

posted @ 2015-06-01 05:34 世界到处都是小星星阅读(106) 评论(0) 推荐(0) 编辑

06 2015 档案