小人物的草稿本

Reverse Linked List II Reverse a linked list from position m to n. Do it in-place and in one-pass.For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4,return 1->4->3->2->5->NULL.No

Permutation Sequence The set [1,2,3,…,n] contains a total of n! unique permutations.By listing and labeling all of the permutations in order,We get the following sequence (ie, for n =

Simplify Path Given an absolute path for a file (Unix-style), simplify it.For example,path = "/home/", => "/home"path = "/a/./b/../../c/", => "/c"class Solution {public: //遇到/.就

Set Matrix Zeroes 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.class Solution {public: //O(1)的存储空间,利用矩阵本身的存储空

Regular Expression Matching Implement regular expression matching with support for '.' and '*'.'.' Matches any single character.'*' Matches zero or more of the preceding element.The mat

Merge k Sorted Lists Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity./** * Definition for singly-linked list. * struct ListNode { *

Longest Substring Without Repeating Characters Given a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeating let

Roman to Integer Given a roman numeral, convert it to an integer.Input is guaranteed to be within the range from 1 to 3999.class Solution {public: int romanToInt(string s) {

Longest Common Prefix Write a function to find the longest common prefix string amongst an array of strings.class Solution {public: string longestCommonPrefix(vector &strs) {

Reverse Nodes in k-Group Given a linked list, reverse the nodes of a linked list k at a time and return its modified list.If the number of nodes is not a multiple of k then left-out nodes

String to Integer (atoi) Implement atoi to convert a string to an integer.Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask your

Palindrome Number Determine whether an integer is a palindrome. Do this without extra space.class Solution {public: bool isPalindrome(int x) { if(x<0) return false

Valid Parentheses Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.The brackets must close in the correct order, "(

Merge Two Sorted Lists 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./** * Definition for

Implement strStr()Implement strStr().Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.Update (2014-11-02):The signature of the

Substring with Concatenation of All Words 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 c

ZigZag Conversion The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibilit

Reverse Integer Reverse digits of an integer.Example1: x = 123, return 321Example2: x = -123, return -321class Solution {public: int reverse(int x) { if(x==0||x>21474836

Remove Nth Node From End of List 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

Remove Duplicates from Sorted Array 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

Remove Element Given an array and a value, remove all instances of that value in place and return the new length.The order of elements can be changed. It doesn't matter what you leave be

Longest Valid Parentheses Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring.For "(()", the longest valid

Search in Rotated Sorted Array Suppose a sorted array is rotated at some pivot unknown to you beforehand.(i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2).You are given a target value t

First Missing Positive 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 i

Sudoku Solver Write a program to solve a Sudoku puzzle by filling the empty cells.Empty cells are indicated by the character '.'.You may assume that there will be only one unique solutio

Jump Game II Given an array of non-negative integers, you are initially positioned at the first index of the array.Each element in the array represents your maximum jump length at that pos

Permutations II 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],

N-Queens The n-queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other.Given an integer n, return all distinct solutions to the n-

Trapping Rain Water Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining.For example, Giv

Median of Two Sorted Arrays There are two sorted arrays nums1 and nums2 of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexity should be O(

Add Two Numbers Total Accepted: 49110 Total Submissions: 219893You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of thei

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

Merge Intervals Given a collection of intervals, merge all overlapping intervals.For example,Given [1,3],[2,6],[8,10],[15,18],return [1,6],[8,10],[15,18].Hide Tags Array Sort

N-Queens II Follow up for N-Queens problem.Now, instead outputting board configurations, return the total number of distinct solutions.Hide Tags BacktrackingHide Similar Prob

Insert Interval Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary).You may assume that the intervals were initially sorted according to

Ugly Number II Write a program to find the n-th ugly number.Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 1, 2, 3, 4, 5, 6, 8, 9, 10, 12 is t

Ugly Number Write a program to check whether a given number is an ugly number.Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while

Plus One Given a non-negative number represented as an array of digits, plus one to the number.The digits are stored such that the most significant digit is at the head of the list.H

Single Number III Given an array of numbers nums, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the two elements that appear only onc

Missing Number Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.For example,Given nums = [0, 1, 3] return 2.Note: