随笔分类 -  LeetCode

摘要:Implement pow(x,n).思路:像string to integer一样。考虑的细节较多。 1.测试用例要考虑基数和指数都为正数、负数和零的情况。 2.注意0的0次方在数学上没有意义。 3.考虑底数为0且指数为负数的处理方法。可以有返回值、全局变量和异常。这里使用全局变量区别... 阅读全文
posted @ 2014-11-26 21:39 vincently 阅读(330) 评论(0) 推荐(0)
摘要:You are climbing a stair case. It takesnsteps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb... 阅读全文
posted @ 2014-11-26 11:19 vincently 阅读(167) 评论(0) 推荐(0)
摘要:Follow up for "Search in Rotated Sorted Array":What ifduplicatesare allowed?Would this affect the run-time complexity? How and why?Write a function to... 阅读全文
posted @ 2014-11-26 10:47 vincently 阅读(252) 评论(0) 推荐(0)
摘要:Suppose a sorted array is rotated at some pivot unknown to you beforehand.(i.e.,0 1 2 4 5 6 7might become4 5 6 7 0 1 2).You are given a target value t... 阅读全文
posted @ 2014-11-26 10:03 vincently 阅读(526) 评论(0) 推荐(0)
摘要:Given two sorted integer arrays A and B, merge B into A as one sorted array.Note:You may assume that A has enough space (size that is greater or equal... 阅读全文
posted @ 2014-11-25 14:46 vincently 阅读(138) 评论(0) 推荐(0)
摘要:Write a function to find the longest common prefix string amongst an array of strings.思路:每个字符串都与第0个字符串比较,设置一个变量,记录每个字符串与第0个字符串不匹配位置的最小值 时间复杂度O(n1+n2... 阅读全文
posted @ 2014-11-24 15:41 vincently 阅读(133) 评论(0) 推荐(0)
摘要:Given two binary strings, return their sum (also a binary string).For example,a ="11"b ="1"Return"100"思路:时间复杂度O(n), 空间复杂度O(1) 1 class Solution { 2 pub... 阅读全文
posted @ 2014-11-04 22:06 vincently 阅读(114) 评论(0) 推荐(0)
摘要:Implementatoito convert a string to an integer.Hint:Carefully consider all possible input cases. If you want a challenge, please do not see below and ... 阅读全文
posted @ 2014-11-04 16:53 vincently 阅读(239) 评论(0) 推荐(0)
摘要:Given a string, determine if it is a palindrome, considering only alphanumericcharacters and ignoring cases.For example,"A man, a plan, a canal: Panam... 阅读全文
posted @ 2014-11-04 14:53 vincently 阅读(158) 评论(0) 推荐(0)
摘要:Given a singlylinked listL: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 examp... 阅读全文
posted @ 2014-11-04 13:17 vincently 阅读(162) 评论(0) 推荐(0)
摘要:Given a linked list, return the node where the cycle begins. If there is no cycle, returnnull.Follow up:Can you solve it without using extra space?思路:... 阅读全文
posted @ 2014-11-04 09:57 vincently 阅读(185) 评论(0) 推荐(0)
摘要:Given a linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?思路:快慢指针的应用。快慢指针指的是移动的步长,即每次向前移动的快慢。例如可以让快指... 阅读全文
posted @ 2014-11-03 20:29 vincently 阅读(150) 评论(0) 推荐(0)
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 @ 2014-11-03 19:36 vincently 阅读(134) 评论(0) 推荐(0)
摘要:Given a linked list, reverse the nodes of a linked listkat a time and return its modified list.If the number of nodes is not a multiple ofkthen left-o... 阅读全文
posted @ 2014-10-29 22:18 vincently 阅读(124) 评论(0) 推荐(0)
摘要:Given a linked list, swap every two adjacent nodes and return its head.For example,Given1->2->3->4, you should return the list as2->1->4->3.Your algor... 阅读全文
posted @ 2014-10-29 17:50 vincently 阅读(159) 评论(0) 推荐(0)
摘要:Given a linked list, remove thenthnode from the end of list and return its head.For example, Given linked list: 1->2->3->4->5, and n = 2. After re... 阅读全文
posted @ 2014-10-29 17:12 vincently 阅读(195) 评论(0) 推荐(0)
摘要:Given a list, rotate the list to the right bykplaces, wherekis non-negative.For example:Given1->2->3->4->5->NULLandk=2,return4->5->1->2->3->NULL.思路一:首... 阅读全文
posted @ 2014-10-29 16:54 vincently 阅读(189) 评论(0) 推荐(0)
摘要:Given a sorted linked list, delete all nodes that have duplicate numbers, leaving onlydistinctnumbers from the original list.For example,Given1->2->3-... 阅读全文
posted @ 2014-10-29 15:06 vincently 阅读(119) 评论(0) 推荐(0)
摘要:Given a sorted linked list, delete all duplicates such that each element appear onlyonce.For example,Given1->1->2, return1->2.Given1->1->2->3->3, retu... 阅读全文
posted @ 2014-10-29 14:19 vincently 阅读(160) 评论(0) 推荐(0)
摘要:Given a linked list and a valuex, partition it such that all nodes less thanxcome before nodes greater than or equal tox.You should preserve the origi... 阅读全文
posted @ 2014-10-29 13:58 vincently 阅读(171) 评论(0) 推荐(0)