Longest Palindromic Substring
摘要：http://www.felix021.com/blog/read.php?2040下面以字符串12212321为例，经过上一步，变成了 S[] = "$#1#2#2#1#2#3#2#1#";然后用一个数组 P[i] 来记录以字符S[i]为中心的最长回文子串向左/右扩张的长度（包括S[i]），比如S...
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2014-04-21 18:02
wf110
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Permutation Sequence
摘要：Permutation SequenceTotal Accepted:6325Total Submissions:29550My SubmissionsThe set[1,2,3,…,n]contains a total ofn! unique permutations.By listing and...
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2014-04-20 19:13
wf110
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Longest Substring Without Repeating Characters
摘要：charTables数组记录字符对应的位置。public class Solution { public int lengthOfLongestSubstring(String s) { if(null==s||0==s.length()) return 0; ...
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2014-04-18 10:43
wf110
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Gray Code
摘要：[leetcode]Gray CodeThe gray code is a binary numeral system where two successive values differ in only one bit. Given a non-negative integer n representing the total number of bits in the code, print the sequence of gray code. A gray code sequence must begin with 0. For example, given n = 2, return
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2014-04-10 10:36
wf110
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Clone Graph
摘要：这里使用BFS来解本题，BFS需要使用queue来保存neighbors但这里有个问题，在clone一个节点时我们需要clone它的neighbors，而邻居节点有的已经存在，有的未存在，如何进行区分？这里我们使用Map来进行区分，Map的key值为原来的node，value为新clone的node，当发现一个node未在map中时说明这个node还未被clone，http://oj.leetcode.com/problems/clone-graph/ 1 public UndirectedGraphNode cloneGraph(UndirectedGraphNode node) {...
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2014-03-21 18:45
wf110
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