01 2017 档案

31. Next Permutation
摘要：Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.If such arrangement is not possible, it must rearrange it as the lowest possible ord... 阅读全文
posted @ 2017-01-24 15:51 copperface 阅读(194) 评论(0) 推荐(0)
30. Substring with Concatenation of All Words
摘要：You are given a string, s, and a list of words, words, that are all of the same length. Find all starting indices of substring(s) in s that is a concatenation of each word in words exactly once and wi... 阅读全文
posted @ 2017-01-24 12:42 copperface 阅读(250) 评论(0) 推荐(0)
Knuth-Morris-Pratt Algorithm
摘要：KMP背景分析普通算法（遍历），会遗忘所有之前比较过的信息，导致每一次移位，都要重新重头比较每一个字符。这将会导致 O(mn)的时间复杂度（m: 关键字符长度，n: 文本string的长度）而KMP算法，则能够保证不去重复比较已经部分匹配的字符，比如序列“abcdabac”，如果“abcd”部分匹配了文本，而在接下来的“a”位置上不匹配，那么算法则会直接跳过4个位置，重新进行比较，而不是移位1个，... 阅读全文
posted @ 2017-01-18 09:43 copperface 阅读(664) 评论(0) 推荐(0)
28. Implement strStr()
摘要：Implement strStr().Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.分析这就是字符串匹配算法算法一：brute forcetime complexity: O(nm)space complexity: O(1)12345... 阅读全文
posted @ 2017-01-17 22:27 copperface 阅读(161) 评论(0) 推荐(0)
24. 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 algorithm should use only constant space. You may not... 阅读全文
posted @ 2017-01-13 14:04 copperface 阅读(153) 评论(0) 推荐(0)
25. Reverse Nodes in k-Group
摘要：123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263/** * Definition for singly-linked list. * struct ListNode { * int val; * L... 阅读全文
posted @ 2017-01-13 14:04 copperface 阅读(162) 评论(0) 推荐(0)
23. Merge k Sorted Lists
摘要：Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity.分析算法1：类似于归并排序，将Merge k 个的问题，拆分成Merge 2 个的子任务，然后递归回溯。算法复杂度 O(nlogn)算法2：使用最小堆。维护一个最大 大小 k 的最小堆，每次从堆顶pop出... 阅读全文
posted @ 2017-01-13 14:03 copperface 阅读(254) 评论(0) 推荐(0)
22. Generate Parentheses
摘要：Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.For example, given n = 3, a solution set is:[ "((()))", "(()())", "(())()", "()(())", "... 阅读全文
posted @ 2017-01-04 22:37 copperface 阅读(165) 评论(0) 推荐(0)
21. 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.分析:就是使用两个指针，让较小的归并到新的list上：代码：方法一：1234567891011121314151617... 阅读全文
posted @ 2017-01-03 22:43 copperface 阅读(192) 评论(0) 推荐(0)
20. Valid Parentheses
摘要：Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.The brackets must close in the correct order, "()" and "()[]{}" are all valid but ... 阅读全文
posted @ 2017-01-03 22:42 copperface 阅读(140) 评论(0) 推荐(0)
19. Remove Nth Node From End of List
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 removing the second node from the end, the linke... 阅读全文
posted @ 2017-01-03 22:42 copperface 阅读(163) 评论(0) 推荐(0)