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Write a program that outputs the string representation of numbers from 1 to n.But for multiples of three it should output “Fizz” instead of the number and for the multiples of five output “Buzz”. Fo

Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order.Example 1:Input: "Let's take LeetCode contes

389. Find the DifferenceGiven two strings s and t which consist of only lowercase letters.String t is generated by random shuffling string s and then add one more letter at a random positi

371. Sum of Two Integers Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -.Example:Given a = 1 and b = 2, return 3.Credits:Special thanks t

Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.You may assume that the array is non-empty and the majority element

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:Your algorithm sho

一提起位运算，人们往往想到它的高效性，无论是嵌入式编程还是优化系统的核心代码，适当的运用位运算总是一种迷人的手段，或者当您求职的时候，在代码中写入适当的位运算也会让您的程序增加一丝亮点，最初当我读《编程之美》求“1的数目”时，我才开始觉得位运算是如此之美，后来读到 《Hacker's Delight》，感慨到Henry S.Warren把位运算运用的如此神出鬼没，很多程序都十分精妙，我觉得在一

https://www.lijinma.com/blog/2014/05/29/amazing-xor/什么是异或？Wikipedia的解释：在逻辑学中，逻辑算符异或（exclusive or）是对两个运算元的一种逻辑析取类型，符号为 XOR 或 EOR 或 ⊕（编程语言中常用^）。但与一般的逻辑或不同，异或算符的值为真仅当两个运算元中恰有一个的值为真，而另外一个的

                                                                                   461. Hamming DistanceThe Hamming distance between two integers is the number of positions at which the corresponding ...

Given a positive integer, output its complement number. The complement strategy is to flip the bits of its binary representation.Note:The given integer is guaranteed to fit within the range

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it

Longest Substring Without Repeating CharactersGiven a string, find the length of the longest substring without repeating characters.Examples:Given “abcabcbb”, the answer is “abc”, which the length is 3

玩了两天生气，又要开始学习啦，打算从leetcode第一道题目开始刷，一周至少三道，其余时间学习项目。保持手感。 不为刷题而刷题，策略是用题号为1的开始顺序刷，对于一道题尝试使用c++和python两种语言多种方法解决问题。开始ing!!!!!!1. Two SumGiven an array of integers, return indices of the two numbers such

Given an array of integers, every element appears twice except for one. Find that single one.Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra

题目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 in place with co

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 below and ask yourself what are the possible input cases

题目Given a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000.Example:Input: “babad”Output: “bab”Note: “aba” is also a valid answer.Example:Input:

题目Write a function that takes an unsigned integer and returns the number of ’1’ bits it has (also known as the Hamming weight).For example, the 32-bit integer ’11’ has binary representation 00000000000

题目Reverse bits of a given 32 bits unsigned integer. For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as 0011100101

题目Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. For example: Given num = 38, the process is like: 3 + 8 = 11, 1 + 1 = 2. Since 2 has only one di

越来越喜欢leetcode的刷题方式了，只需要写核心的代码，不用为输入输出多一个空格或者少一个空格浪费时间，而且大多题目你需要用vector或者链表解题而不是数组，更加节省空间。题目Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together th

Determine whether an integer is a palindrome. Do this without extra space.click to show spoilers. Some hints:Could negative integers be palindromes? (ie, -1)If you are thinking of converting the in

Reverse digits of an integer.Example1: x = 123, return 321 Example2: x = -123, return -321 click to show spoilers. Note: The input is assumed to be a 32-bit signed integer. Your function should ret

Median of Two Sorted ArraysThere 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(log (m+n)).Exam

声明：题目解法使用c++和python两种，练习在于如何将c++代码转换为python代码。题目Given a string containing just the characters ‘(‘, ‘)’, ‘{‘, ‘}’, ‘[’ and ‘]’, determine if the input string is valid.The brackets must close in the corr

题目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 in place with constant memory.The ord

题目Implement strStr(). Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. 题意从字符串haystack找到字符串needle第一次出现的首地址。思路基本思路： 原字符串指针逐步递增，每指向一个字符，从当前字符进行比较

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.Her

xuna小记：题目解法使用c++和Python两种，重点侧重在于解题思路和如何将解法用python语言实现。题目Given a roman numeral, convert it to an integer.Input is guaranteed to be within the range from 1 to 3999.题意给你一个罗马数字，转换为对应的阿拉伯数字，罗马数字的范围为1~3999。分

xuna小记：题目解法使用c++和Python两种，重点侧重在于解题思路和如何将解法用python语言实现。同类题目：罗马数字转化阿拉伯数字http://blog.youkuaiyun.com/xunalove/article/details/77676382题目Given an integer, convert it to a roman numeral.Input is guaranteed to be w

题目The count-and-say sequence is the sequence of integers with the first five terms as following:1112112111112211 is read off as “one 1” or 11. 11 is read off as “two 1s” or 21. 21 is read off a

周末了，说好的每周三道题题目66Given 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.T

题目Find the contiguous subarray within an array (containing at least one number) which has the largest sum.For example, given the array [-2,1,-3,4,-1,2,1,-5,4], the contiguous subarray [4,-1,2,1] has t

题目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

xuna小记：题目解法使用c++和Python两种，重点侧重在于解题思路和如何将解法用python语言实现。题目Write a function to find the longest common prefix string amongst an array of strings. 题意找出最长公共前缀字符串思路找出长度最短的字符串作为模板字符串，枚举模板字符串的每一个字符，比较所有字符串同一位置

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 addition

题目Given two binary trees, write a function to check if they are equal or not.Two binary trees are considered equal if they are structurally identical and the nodes have the same value. 题意给你两个二叉树p和q，写一个

题意Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).For example, this binary tree [1,2,2,3,4,4,3] is symmetric: 1 / \ 2 2 / \ / \3 4 4 3But th

题目Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.题意给你一个二叉树，求出二叉树的最大的深度。分析递归模型为：f(root)==0

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).For example: Given binary tree [3,9,20,null,null,15,7