Errant_Xia-优快云博客

原创 Leetcode : Palindrome Number

Palindrome NumberJan 4 '12 Determine whether an integer is a palindrome. Do this without extra space. 思路： 1）这题其实可以参照Leetcode : Reverse Integer(http://blog.youkuaiyun.com/errant_xia/article/

2013-03-14 22:18:44 789

原创 Leetcode : String to Integer (atoi)

String to Integer (atoi)Dec 27 '11 Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and a

2013-03-07 22:11:41 797

原创 [面试题] 判断一个单链表是否有环

题目：已知一个单向链表的头指针是 Node* pHead，如何判断该单项链表是否有环路！ Note 1：看了很多文章中都是直接说定义两个指针，一个每次走一步（PA），一个每次走两步（PB），看最终是否相遇（有环），或者有一个指针指向NULL（无环）。看完之后有点懵，不知道为什么这样就能解决问题。无奈之下只要先证明方法的可行性了。证明：（反证法）如果链表中没有环，则

2013-03-07 00:18:00 1076

原创 Leetcode : Reverse Integer

Reverse IntegerDec 26 '11 Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 Note : 这道题比较简单，很多计算机语言的初级教程的习题中都会遇到，但需要对一种特殊情况考虑到（x = 0），也就是当编程时

2013-03-05 22:36:20 807

原创 Leetcode : ZigZag Conversion

ZigZag ConversionDec 6 '11 The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better leg

2013-03-05 22:20:20 2270 1

原创 Leetcode : Longest Palindromic Substring

Longest Palindromic SubstringNov 11 '11 Given a string S, find the longest palindromic substring in S. You may assume that the maximum length of S is 1000, and there exists one unique longest

2013-03-04 23:54:11 558

原创 Leetcode : Add Two Numbers

Add Two NumbersNov 1 '11 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 digit. Add the two

2013-02-28 00:08:09 565

原创 Leetcode : Longest Consecutive Sequence

Given an unsorted array of integers, find the length of the longest consecutive elements sequence. For example, Given [100, 4, 200, 1, 3, 2], The longest consecutive elements sequence is [1,

2013-02-28 00:00:19 537

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