qq_34609108的博客

Given a binary treestruct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next;}Populate each next pointer to point to its next right node. If there is no next right node...

Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order red, white and blue.Here, we will use the inte...

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:Integers in each row are sorted from left to right.The first integer of each row is ...

Follow up for "Unique Paths":Now consider if some obstacles are added to the grids. How many unique paths would there be?An obstacle and empty space is marked as 1 and 0 respectively in the grid.For e...

A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).The robot can only move either down or right at any point in time. The robot is trying to reach the bott...

Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.Example 1:Input: 1->2->3->3->4->4->5Output: 1->2-&g...

Given two words word1 and word2, find the minimum number of operations required to convert word1 to word2.You have the following 3 operations permitted on a word:Insert a characterDelete a characterRe...

Given a sorted linked list, delete all duplicates such that each element appear only once.Example 1:Input: 1->1->2Output: 1->2Example 2:Input: 1->1->2->3->3Output: 1->2->...

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 ]...

Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.If the last word does not exist, return 0.Note: A word is defined a...

Given two binary strings, return their sum (also a binary string).For example,a = "11"b = "1"Return "100".class Solution {public: string addBinary(string a, string b) { swap( a, b); int lenA = ...

Given a non-negative integer represented as a non-empty array of digits, plus one to the integer.You may assume the integer do not contain any leading zero, except the number 0 itself.The digits are s...

Given a collection of numbers that might contain duplicates, return all possible unique permutations.For example,[1,1,2] have the following unique permutations:[ [1,1,2], [1,2,1], [2,1,1]]转自 ： ...

Given a collection of distinct numbers, return all possible permutations.For example,[1,2,3] have the following permutations:[ [1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], [3,2,1]]class ...

Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.Note: You can only move either down or right at any...

Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).Example:Input: S = "ADOBECODEBANC", T = "ABC"Output: "BANC"Note:If there i...

转自 ：  https://blog.youkuaiyun.com/feliciafay/article/details/42959119Given a string S and a string T, count the number of distinct subsequences of S which equals T.A subsequence of a string is a new string ...

Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.Example 1:Input: s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"Output: trueExample 2:Input: s1 = "aabcc", s2 = "dbbca", s3...

Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level).For example:Given binary tree [3,9,20,null,null,15,7], 3 / \ 9 20 / \...

Reverse a linked list from position m to n. Do it in one-pass.Note: 1 ≤ m ≤ n ≤ length of list.Example:Input: 1->2->3->4->5->NULL, m = 2, n = 4Output: 1->4->3->2->5->NUL...

Reverse a singly linked list.Example:Input: 1->2->3->4->5->NULLOutput: 5->4->3->2->1->NULLFollow up:A linked list can be reversed either iteratively or recursively. Cou...

Given a binary tree, return the inorder traversal of its nodes' values.Example:Input: [1,null,2,3] 1 \ 2 / 3Output: [1,3,2]Follow up: Recursive solution is trivial, could you do i...

Given a collection of integers that might contain duplicates, nums, return all possible subsets (the power set).Note: The solution set must not contain duplicate subsets.Example:Input: [1,2,2]Output:...

Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing only 1's and return its area.Example:Input:[ ["1","0","1","0","0"], ["1","0","1",&q

Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.(i.e., [0,0,1,2,2,5,6] might become [2,5,6,0,0,1,2]).You are given a target value to search. If found in t...

Given a sorted array nums, remove the duplicates in-place such that duplicates appeared at most twice and return the new length.Do not allocate extra space for another array, you must do this by modif...

Given a 2D board and a word, find if the word exists in the grid.The word can be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horizontally or vertically nei...

Given a set of distinct integers, nums, return all possible subsets (the power set).Note: The solution set must not contain duplicate subsets.Example:Input: nums = [1,2,3]Output:[ [3],  [1],  [2...

Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.Example:Input: n = 4, k = 2Output:[ [2,4], [3,4], [2,3], [1,2], [1,3], [1,4],]class Solution {...

Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order.For example,Given the following matrix:[ [ 1, 2, 3 ], [ 4, 5, 6 ], [ 7, 8, 9 ]]You should r...

Implement wildcard pattern matching with support for '?' and '*'.'?' Matches any single character.'*' Matches any sequence of characters (including the empty sequence).The matching should cover the...

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.Example:Input: 1->2->4, 1->3->4Output: 1->1->2->3->4

我不会！！！！！！就是不会！！ 暴力搜索超时：超时代码class Solution {public: int longestValidParentheses(string s) { return findLong(s); }private: int findLong(string s){ int subLen = s.length(); if (IsPar

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

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.

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list.k is a positive integer and is less than or equal to the length of the linked list. If the number o

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

Divide two integers without using multiplication, division and mod operator.If it is overflow, return MAX_INT.class Solution{public: int divide(int dividend, int divisor) { if (divisor == 0 ||

Given an array and a value, remove all instances of that value in-place and return the new length.Do not allocate extra space for another array, you must do this by modifying the input array in-

Given a sorted array, remove the duplicates in-place such that each element appear only once and return the new length.Do not allocate extra space for another array, you must do this by modifyin