Hooting的码农笔记本

Given a linked list, return the node where the cycle begins. If there is no cycle, return null.Follow up:Can you solve it without using extra space?Proof:

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

Gas Station Total Accepted: 14176 Total Submissions: 57777My SubmissionsThere are N gas stations along a circular route, where the amount of gas at station i is gas[i].You have a car w

Candy There are N children standing in a line. Each child is assigned a rating value.You are giving candies to these children subjected to the following requirements:Each child must

Single Number Total Accepted: 24874 Total Submissions: 55282My SubmissionsGiven an array of integers, every element appears twice except for one. Find that single one.Note:Your algor

Given a linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?My Answer:/** * Definition for singly-linked list. * class ListNode { *

Given a singly linked list L: 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 example,Given {1,2,3,4}, reorder it to 

Given a binary tree, return the postorder traversal of its nodes' values.For example:Given binary tree {1,#,2,3}, 1 \ 2 / 3return [3,2,1].Note: Recursive solut

Copy List with Random Pointer 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 of the

Given a binary tree, return the preorder traversal of its nodes' values.For example:Given binary tree {1,#,2,3}, 1 \ 2 / 3return [1,2,3].Note: Recursive soluti

Sort a linked list using insertion sort.My Answer:

Given a string s and a dictionary of words dict, add spaces in s to construct a sentence where each word is a valid dictionary word.Return all such possible sentences.For example, givens = "

Given an input string, reverse the string word by word.For example,Given s = "the sky is blue",return "blue is sky the".Clarification:What constitutes a word?A sequence of non-spac

Given n points on a 2D plane, find the maximum number of points that lie on the same straight line.

Evaluate the value of an arithmetic expression in Reverse Polish Notation.Valid operators are +, -, *, /. Each operand may be an integer or another expression.Some examples:

Sort a linked list in O(n log n) time using constant space complexity.My Answer:

Word BreakGiven a string s and a dictionary of words dict, determine if s can be segmented into a space-separated sequence of one or more dictionary words.For example, givens = "leetco

Sum Root to Leaf NumbersGiven a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number.An example is the root-to-leaf path 1->2->3 which represents th