Sheryl Wang - 博客园

Reverse Linked List II

摘要： Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2- 阅读全文

posted @ 2016-04-26 21:46 Sheryl Wang 阅读(190) 评论(0) 推荐(0)

Longest Common Prefix

摘要： Write a function to find the longest common prefix string amongst an array of strings. 这是一道字符串的简单题.思路也非常简单,基本都是brute force的解法.具体解法分为:按列扫和按行扫两种. 按列扫,是每阅读全文

posted @ 2016-04-26 10:23 Sheryl Wang 阅读(167) 评论(0) 推荐(0)

Swap Nodes in Pairs

摘要： Given a linked list, swap every two adjacent nodes and return its head. For example,Given 1->2->3->4, you should return the list as 2->1->4->3. Your a 阅读全文

posted @ 2016-04-25 14:55 Sheryl Wang 阅读(131) 评论(0) 推荐(0)

Merge k Sorted Lists

摘要： Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity. 这是一道hard的题目，但是其实思路并不复杂，做起来也比较有趣。做完Merge Two Sorted 阅读全文

posted @ 2016-04-24 16:36 Sheryl Wang 阅读(165) 评论(0) 推荐(0)

Kth Largest Element in an Array

摘要：利用最小堆解决，代码如下：另外一个是使用快排的partition的方法（可见剑指offer167页），寻找index为k-1的pivot ，原理是一次partition之后，pivot左边的数都小于等于pivot，右边的数都大于等于pivot，所以pivot左边加pivot形成index个数组中阅读全文

posted @ 2016-04-24 12:00 Sheryl Wang 阅读(198) 评论(0) 推荐(0)

Merge Two Sorted Lists

摘要： Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists. 这题与Add T 阅读全文

posted @ 2016-04-24 11:34 Sheryl Wang 阅读(148) 评论(0) 推荐(0)

Add Two Numbers

摘要： You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single 阅读全文

posted @ 2016-04-23 20:44 Sheryl Wang 阅读(171) 评论(0) 推荐(0)

Remove Nth Node From End of List 和链表题目总结

摘要： Given a linked list, remove the nth node from the end of list and return its head. For example, Given linked list: 1->2->3->4->5, and n = 2. After rem 阅读全文

posted @ 2016-04-23 17:25 Sheryl Wang 阅读(254) 评论(0) 推荐(0)

Longest Substring Without Repeating Characters

摘要：题意为给出一个字符串，找出其中没有重复字符的最长子序列的长度。brute force的复杂度为O(n^3).依次查找每个子字符串是否含有重复字符，并比较长度。开始看到题目，想用DP解决，在已有目前最长子序列的情况下，比较把当前字符串放入和不放入，哪个子序列长度会更大，但是这种解法的复杂度为O(n^2 阅读全文

posted @ 2016-04-18 23:07 Sheryl Wang 阅读(147) 评论(0) 推荐(0)

Construct Binary Tree from Inorder and Postorder Traversal

摘要：思路和依据前序遍历和中序遍历重建树的思路一样，复杂度也一致，代码如下：阅读全文

posted @ 2016-04-18 20:14 Sheryl Wang 阅读(152) 评论(0) 推荐(0)