lettuan

2017年2月26日

摘要： Given a collection of intervals, merge all overlapping intervals. For example, Given [1,3],[2,6],[8,10],[15,18], return [1,6],[8,10],[15,18]. 思路1：现将左右阅读全文

posted @ 2017-02-26 03:35 lettuan 阅读(306) 评论(0) 推荐(0)

Leetcode 23. Merge K sorted lists

摘要： Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity. 思路：参考：http://www.cnblogs.com/zuoyuan/p/3772372.html 阅读全文

posted @ 2017-02-26 01:39 lettuan 阅读(132) 评论(0) 推荐(0)

Leetcode 12,13. Interger to Roman, Roman to Integer

摘要： Given a roman numeral, convert it to an integer. Input is guaranteed to be within the range from 1 to 3999. 思路：先建立一个对应的dict。注意转换规则中的特例，比如XL (=50-10), 阅读全文

posted @ 2017-02-26 01:15 lettuan 阅读(123) 评论(0) 推荐(0)

2017年2月25日

Leetcode 4. Median of Two Sorted Arrays

摘要： There are two sorted arrays nums1 and nums2 of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexity sh 阅读全文

posted @ 2017-02-25 14:57 lettuan 阅读(213) 评论(0) 推荐(0)

Leetcode 76. Edit Distance

摘要： Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.) You have 阅读全文

posted @ 2017-02-25 03:24 lettuan 阅读(179) 评论(0) 推荐(0)

2017年2月21日

Leetcode 156. Binary Tree Upside Down

摘要： Given a binary tree where all the right nodes are either leaf nodes with a sibling (a left node that shares the same parent node) or empty, flip it up 阅读全文

posted @ 2017-02-21 13:47 lettuan 阅读(332) 评论(0) 推荐(0)

Leetcode 151. Reverse Words in a String

摘要： Given an input string, reverse the string word by word. For example, Given s = "the sky is blue", return "blue is sky the". Update (2015-02-12): For C 阅读全文

posted @ 2017-02-21 04:21 lettuan 阅读(101) 评论(0) 推荐(0)

2017年2月20日

Leetcode 143. Reorder List

摘要： Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→… You must do this in-place without altering the nodes' values. For 阅读全文

posted @ 2017-02-20 13:01 lettuan 阅读(126) 评论(0) 推荐(0)

Leetcode 138. Copy List with random pointer

摘要： A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null. Return a deep copy 阅读全文

posted @ 2017-02-20 10:18 lettuan 阅读(165) 评论(0) 推荐(0)

Leetcode 127. Word Ladder

摘要：思路：阅读全文

posted @ 2017-02-20 06:39 lettuan 阅读(159) 评论(0) 推荐(0)

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