08 2014 档案
摘要：题目：Given a collection of numbers that might contain duplicates, return all possible unique permutations.For example,[1,1,2] have the following unique...
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摘要：题目： 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 be...
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摘要：题目：Implement strStr().Returns a pointer to the first occurrence of needle in haystack, or null if needle is not part of haystack.题解：其实我觉得这题。。为啥不给个更明确...
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摘要：题目：Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.If such arrangement is not pos...
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摘要：题目：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 seque...
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摘要：题目：Given an array of words and a length L, format the text such that each line has exactly L characters and is fully (left and right) justified. You ...
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摘要：题目：Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.)You ha...
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摘要：题目：Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively.Below is one possible represent...
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摘要：题目：A message containing letters from A-Z is being encoded to numbers using the following mapping:'A' -> 1'B' -> 2...'Z' -> 26Given an encoded message...
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摘要：题目：Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.For example,Given:s1 = "aabcc",s2 = "dbbca",When s3 = "aadbbcbcac", r...
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摘要：题目：Given a string S and a string T, count the number of distinct subsequences of T in S.A subsequence of a string is a new string which is formed fro...
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摘要：题目：Given n points on a 2D plane, find the maximum number of points that lie on the same straight line.题解：这道题就是给你一个2D平面，然后给你的数据结构是由横纵坐标表示的点，然后看哪条直线上的点...
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摘要：题目：Validate if a given string is numeric.Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => trueNote: It is intended fo...
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摘要：题目：Implement wildcard pattern matching with support for '?' and '*'.'?' Matches any single character.'*' Matches any sequence of characters (includin...
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摘要：题目：Implement regular expression matching with support for '.' and '*'.'.' Matches any single character.'*' Matches zero or more of the preceding elem...
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摘要：题目：Given two words (start and end), and a dictionary, find all shortest transformation sequence(s) from start to end, such that:Only one letter can b...
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摘要：题目：Given two words (start and end), and a dictionary, find the length of shortest transformation sequence from start to end, such that:Only one letter...
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摘要：题目：Given a string s, partition s such that every substring of the partition is a palindrome.Return the minimum cuts needed for a palindrome partition...
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摘要：题目：Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level ...
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摘要：题目：Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root).F...
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摘要：题目：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...
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摘要：题目：Two elements of a binary search tree (BST) are swapped by mistake.Recover the tree without changing its structure.Note:A solution using O(n) space...
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摘要：题目：Given a binary tree, determine if it is a valid binary search tree (BST).Assume a BST is defined as follows:The left subtree of a node contains on...
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摘要：题目：Given two numbers represented as strings, return multiplication of the numbers as a string.Note: The numbers can be arbitrarily large and are non-...
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摘要：题目：Follow up for "Remove Duplicates":What if duplicates are allowed at most twice?For example,Given sorted array A = [1,1,1,2,2,3],Your function shou...
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摘要：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...
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摘要：题目：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 f...
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摘要：题目：Follow up for problem "Populating Next Right Pointers in Each Node".What if the given tree could be any binary tree? Would your previous solution ...
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摘要：题目：Given two binary strings, return their sum (also a binary string).For example,a = "11"b = "1"Return "100".题解：二进制加法都是从最低位（从右加到左）。所以对两个字符串要从最后一位开始加，...
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摘要：题目：The gray code is a binary numeral system where two successive values differ in only one bit.Given a non-negative integer n representing the total ...
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摘要：题目：The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...1 is read off as "one 1" or 11.11 is read ...
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摘要：题目：Determine whether an integer is a palindrome. Do this without extra space.click to show spoilers.Some hints:Could negative integers be palindromes...
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摘要：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 lo...
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摘要：题目：Given a collection of numbers, return all possible permutations.For example,[1,2,3] have the following permutations:[1,2,3], [1,3,2], [2,1,3], [2,...
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摘要：题目：There are N gas stations along a circular route, where the amount of gas at station i is gas[i].You have a car with an unlimited gas tank and it c...
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摘要：题目：Given an input string, reverse the string word by word.For example,Given s = "the sky is blue",return "blue is sky the".click to show clarificatio...
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摘要：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 s...
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摘要：题目：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 i...
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摘要：题目：Given an index k, return the kth row of the Pascal's triangle.For example, given k = 3,Return [1,3,3,1].Note:Could you optimize your algorithm to ...
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摘要：题目：Given numRows, generate the first numRows of Pascal's triangle.For example, given numRows = 5,Return[ [1], [1,1], [1,2,1], [1,3,3,1], [1...
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摘要：题目：Given a triangle, find the minimum path sum from top to bottom. Each step you may move to adjacent numbers on the row below.For example, given the...
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摘要：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 foll...
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摘要：题目：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:[[ ...
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摘要：题目：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 pa...
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摘要：题目：Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; }Populate each next po...
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摘要：题目：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 spa...
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摘要：题目： 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 a...
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摘要：题目：You are climbing a stair case. It takes n steps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you...
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摘要：题目：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...
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摘要：题目：You are given an n x n 2D matrix representing an image.Rotate the image by 90 degrees (clockwise).Follow up:Could you do this in-place?题解：这道题就是考察很...
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摘要：题目：Given a roman numeral, convert it to an integer.Input is guaranteed to be within the range from 1 to 3999. 题解：这道题跟interger to roman一样都得先熟悉罗马数字的规则。罗...
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摘要：题目：Given an integer, convert it to a roman numeral.Input is guaranteed to be within the range from 1 to 3999.题解：这道题。。还有哪个roman to integer。。第一件事 就是先把r...
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摘要：题目：Reverse digits of an integer.Example1: x = 123, return 321Example2: x = -123, return -321click to show spoilers.Have you thought about this?Here...
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摘要：题目：Given a binary tree, find the maximum path sum.The path may start and end at any node in the tree.For example:Given the below binary tree, 1...
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摘要：题目：Given a string containing only digits, restore it by returning all possible valid IP address combinations.For example:Given "25525511135",return [...
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摘要：题目：Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T.Each ...
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摘要：题目：Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The same re...
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摘要：题目：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 ...
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摘要：题目：Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules.The Sudoku board could be partially filled, where empty cells are filled ...
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摘要：题目：Given a string s, partition s such that every substring of the partition is a palindrome.Return all possible palindrome partitioning of s.For exam...
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摘要：题目：Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.For example,"A man, a plan, a canal: ...
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摘要：题目：Given 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 w...
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摘要：题目：Given inorder and postorder traversal of a tree, construct the binary tree.Note:You may assume that duplicates do not exist in the tree.题解：这道题跟pre...
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摘要：题目：Given preorder and inorder traversal of a tree, construct the binary tree.Note:You may assume that duplicates do not exist in the tree.题解： 1 ...
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摘要：题目：Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.题解：之前做过一道是从sorted array转换到BinarySearc...
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摘要：题目： Given n, generate all structurally unique BST's (binary search trees) that store values 1...n.For example,Given n = 3, your program should return...
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摘要：下面应用转自Wikipedia（http://zh.wikipedia.org/wiki/%E5%8D%A1%E5%A1%94%E5%85%B0%E6%95%B0）：组合数学中有非常多的组合结构可以用卡塔兰数来计数。在Richard P. Stanley的Enumerative Combinato...
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摘要：题目：Given n, how many structurally unique BST's (binary search trees) that store values 1...n?For example,Given n = 3, there are a total of 5 unique B...
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摘要：题目：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 "ad...
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