题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement us…

题目: Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. For example,Given n = 3, You should return the following matrix: [ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ] ] 代码: class Solution { public: vector<vector<…

题目: Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place. click to show follow up. Follow up: Did you use extra space?A straight forward solution using O(mn) space is probably a bad idea.A simple improvement us…

题目: 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 palindromic substring. 代码: class Solution { public: string longestPalindrome(string s) { const…

题意: 给出老虎的起始点.方向和驴的起始点.方向.. 规定老虎和驴都不会走自己走过的方格,并且当没路走的时候,驴会右转,老虎会左转.. 当转了一次还没路走就会停下来.. 问他们有没有可能在某一格相遇.. 思路: 模拟,深搜.. 用类似时间戳的东西给方格标记上,表示某一秒正好走到该方格.. 最后遍历一下驴在某一格方格标记时间是否和老虎在该格标记的时间一样,一样代表正好做过这里了.. 还有一种情况就是老虎或驴一直停在那里,那就算不相等,也是可以的.. Tips: 我一直忘了老虎或驴停下来的情况,这样…

题目: Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order. You may assume no duplicates in the array. Here are few examples.[1,3,5,6], 5 → 2[1,3,5,6],…

题目: Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 代码: class Solution { public: int firstMissingPos…

题目: Sort a linked list using insertion sort. 代码: /** * Definition for singly-linked list. * struct ListNode { * int val; * ListNode *next; * ListNode(int x) : val(x), next(NULL) {} * }; */ class Solution { public: ListNode* insertionSortList(ListNode…

题目: Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array. Note:You may assume that nums1 has enough space (size that is greater or equal to m + n) to hold additional elements from nums2. The number of elements i…

题目: Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ / \ 7 2 5 1 return [ [5,4,11,2], [5,8,4,5] ] 代码: /** * Defini…