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problem description: You are the public relations manager for a chocolate manufacturer. Unfortunately, the company’s image has suffered because customers think the owner is cheap and miserly. You hope

这次code jam一共四大题。 下面分别详细展示A+B两道题的解题思路及Python代码。Problem A. Cody’s Jams 题目： ProblemCody, the owner of the legendary Cody’s Jams store, is planning a huge jam sale. To make things simple, he has decided

Operating system Coding language: C++ Algorithms Sorting Data structures Mathematics Graphs Recursion System Design Linux CudaLeetcode: 5*100 day (1*easy+3*medium+1*hard)100天的学习提升计划，每半个月至少进行一次面试实战。待续。。。...

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 orde

Given a linked list, swap every two adjacent nodes and return its head.For example, Given 1->2->3->4, you should return the list as 2->1->4->3.Your algorithm should use only constant space. You may no

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:[ "((()))", "(()())", "(())()", "()(())", "(

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 removing the second node from the end, the linked list be

Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target.Note: The solution set mu

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 legibility)P A H NA P L S I I GY

Given a digit string, return all possible letter combinations that the number could represent.A mapping of digit to letters (just like on the telephone buttons) is given below.Input:Digit string "23"O

Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly

题目： Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero.Note: The solution set must not contain d

题目： Given an integer, convert it to a roman numeral.Input is guaranteed to be within the range from 1 to 3999. 题意： 把数字转换成罗马数字数字与罗马数字相互表示的原则： 方法一：119msclass Solution(object): def intToRoman(

title: Given n non-negative integers a1, a2, …, an, where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints of line i is at (i, ai) and (i, 0). Find

题目： Implement atoi to convert a string to an integer. 实现atoi函数 Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possi

Title: Given a string, find the length of the longest substring without repeating characters.Examples:Given "abcabcbb", the answer is "abc", which the length is 3.Given "bbbbb", the answer is "b", wit

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:Inp

题目描述： 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 re

Given two non-empty binary trees s and t, check whether tree t has exactly the same structure and node values with a subtree of s. A subtree of s is a tree consists of a node in s and all of this node’

In MATLAB, there is a very useful function called ‘reshape’, which can reshape a matrix into a new one with different size but keep its original data.You’re given a matrix represented by a two-dimensio

Given a binary tree, return the tilt of the whole tree.The tilt of a tree node is defined as the absolute difference between the sum of all left subtree node values and the sum of all right subtree nod

Given an array of 2n integers, your task is to group these integers into n pairs of integer, say (a1, b1), (a2, b2), …, (an, bn) which makes sum of min(ai, bi) for all i from 1 to n as large as possibl

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 contest"Output

You are given a string representing an attendance record for a student. The record only contains the following three characters:‘A’ : Absent. ‘L’ : Late. ‘P’ : Present. A student could be rewarded i

Given a binary tree, you need to compute the length of the diameter of the tree. The diameter of a binary tree is the length of the longest path between any two nodes in a tree. This path may or may no

Divide two integers without using multiplication, division and mod operator.If it is overflow, return MAX_INT.方法一：72ms 解题思路：不许用乘、除和求余实现两数的相除。那就只能用加和减了。正常思路是被除数一个一个的减除数，直到剩下的数比除数小为止，就得到了结果。这样是无法ac的，因为时

Given a string and an integer k, you need to reverse the first k characters for every 2k characters counting from the start of the string. If there are less than k characters left, reverse all of them.

Given a binary search tree with non-negative values, find the minimum absolute difference between values of any two nodes.Example:Input: 1 \ 3 / 2Output:1Explanation:The minimum abs

Given a word, you need to judge whether the usage of capitals in it is right or not.We define the usage of capitals in a word to be right when one of the following cases holds:All letters in this word

We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself.Now, given an integer n, write a function that returns true when it is a perfect n

Given an integer, return its base 7 string representation.Example 1:Input: 100Output: "202"Example 2:Input: -7Output: "-10"Note: The input will be in range of [-1e7, 1e7].实现七进制方法一：68msclass Solution(

Given a binary search tree (BST) with duplicates, find all the mode(s) (the most frequently occurred element) in the given BST.Assume a BST is defined as follows:The left subtree of a node contains onl

Given a List of words, return the words that can be typed using letters of alphabet on only one row’s of American keyboard like the image below.American keyboard Example 1:Input: ["Hello", "Alaska", "

For a web developer, it is very important to know how to design a web page’s size. So, given a specific rectangular web page’s area, your job by now is to design a rectangular web page, whose length L

Given a binary array, find the maximum number of consecutive 1s in this array.Example 1:Input: [1,1,0,1,1,1]Output: 3Explanation: The first two digits or the last three digits are consecutive 1s.

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 of a 32-b

Winter is coming! Your first job during the contest is to design a standard heater with fixed warm radius to warm all the houses.Now, you are given positions of houses and heaters on a horizontal line,

You are given a map in form of a two-dimensional integer grid where 1 represents land and 0 represents water. Grid cells are connected horizontally/vertically (not diagonally). The grid is completely s

The Hamming distance between two integers is the number of positions at which the corresponding bits are different.Given two integers x and y, calculate the Hamming distance.Note: 0 ≤ x, y < 231.Examp

Given a non-empty string check if it can be constructed by taking a substring of it and appending multiple copies of the substring together. You may assume the given string consists of lowercase Englis