09 2019 档案
摘要：Write a function to find the longest common prefix string amongst an array of strings. If there is no common prefix, return an empty string "". Exampl
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摘要：Given a 32-bit signed integer, reverse digits of an integer. Example 1: Example 2: Example 3: Note:Assume we are dealing with an environment which cou
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摘要：Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid. An input string is valid if: No
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摘要：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/ve
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摘要：Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) Yo
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摘要：Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. For example, two is written as II in Roman numeral, just two one's
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摘要：Given a collection of numbers that might contain duplicates, return all possible unique permutations. Example: 思路
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摘要：Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. Example: 思路：回溯
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摘要：Given a collection of distinct integers, return all possible permutations. Example: 思路一：二话不说，经典题， 回溯。 思路二：
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摘要：Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers. If such arrangement is not possib
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摘要：You need to construct a string consists of parenthesis and integers from a binary tree with the preorder traversing way. The null node needs to be rep
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摘要：Implement function ToLowerCase() that has a string parameter str, and returns the same string in lowercase. Example 1: Input: "Hello" Output: "hello"
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摘要：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: 思
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摘要：Given two arrays, write a function to compute their intersection. Example 1: Example 2: Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4] Output: [9,4] Exam
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摘要：Given two arrays, write a function to compute their intersection. Example 1: Example 2: Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4] Output: [4,9] Exam
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摘要：You are a product manager and currently leading a team to develop a new product. Unfortunately, the latest version of your product fails the quality c
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摘要：Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target value. Your algorithm's runtime com
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摘要：Given a matrix of m x n elements (m rows, n columns), return all elements of the matrix in spiral order. Example 1: Example 2:
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摘要：Given a positive integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. Example: 思路：一次填充矩阵外围一轮数。
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摘要：Given an input string (s) and a pattern (p), implement wildcard pattern matching with support for '?' and '*'. The matching should cover the entire in
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摘要：Given an input string (s) and a pattern (p), implement regular expression matching with support for '.' and '*'. The matching should cover the entire
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摘要：The demons had captured the princess (P) and imprisoned her in the bottom-right corner of a dungeon. The dungeon consists of M x N rooms laid out in a
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摘要：Determine if a 9x9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules: A partially filled sudoku which
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摘要：The count-and-say sequence is the sequence of integers with the first five terms as following: 1 is read off as "one 1" or 11.11 is read off as "two 1
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摘要：On a 2-dimensional grid, there are 4 types of squares: 1 represents the starting square. There is exactly one starting square. 2 represents the ending
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摘要：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 any p
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摘要：Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, ...) which sum to n. Example 1: Example 2: 思路：d
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摘要：Given several boxes with different colors represented by different positive numbers. You may experience several rounds to remove boxes until there is
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摘要：Given n balloons, indexed from 0 to n-1. Each balloon is painted with a number on it represented by array nums. You are asked to burst all the balloon
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摘要：Write a program to find the node at which the intersection of two singly linked lists begins. For example, the following two linked lists: begin to in
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摘要：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 maxim
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摘要：题目描述 给定一个数组和滑动窗口的大小，找出所有滑动窗口里数值的最大值。例如，如果输入数组{2,3,4,2,6,2,5,1}及滑动窗口的大小3，那么一共存在6个滑动窗口，他们的最大值分别为{4,4,6,6,6,5}； 针对数组{2,3,4,2,6,2,5,1}的滑动窗口有以下6个： {[2,3,4]
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摘要：题目描述 给你一根长度为n的绳子，请把绳子剪成m段（m、n都是整数，n>1并且m>1），每段绳子的长度记为k[0],k[1],...,k[m]。请问k[0]xk[1]x...xk[m]可能的最大乘积是多少？例如，当绳子的长度是8时，我们把它剪成长度分别为2、3、3的三段，此时得到的最大乘积是18。
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摘要：题目描述 请实现一个函数用来找出字符流中第一个只出现一次的字符。例如，当从字符流中只读出前两个字符"go"时，第一个只出现一次的字符是"g"。当从该字符流中读出前六个字符“google"时，第一个只出现一次的字符是"l"。 输出描述: 如果当前字符流没有存在出现一次的字符，返回#字符。 请实现一个函
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摘要：Given an unsorted array of integers, find the number of longest increasing subsequence. Example 1: Example 2: Note: Length of the given array will be
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摘要：Given an array with n objects colored red, white or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the or
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摘要：You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed. All houses at this place are ar
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摘要：You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping yo
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摘要：Given a set of distinct integers, nums, return all possible subsets (the power set). Note: The solution set must not contain duplicate subsets. Exampl
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摘要：题目描述 对于输入的字符串，从左到右扫描字符串，如果存在由三个以上（包括三个）连续相同字符组成的子串，就将这个子串从原串中去掉，并将原有字符串剩下的部分拼接到一起。重复上述过程，直到无法去掉任何子串 输入描述: 输入的字符串 输出描述: 最后剩下的子串 示例1 输入 AAABCCDDDCB 输出 B
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摘要：Given two words word1 and word2, find the minimum number of operations required to convert word1 to word2. You have the following 3 operations permitt
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摘要：时间限制：1秒 空间限制：262144K 时间限制：1秒 空间限制：262144K 给定两个-100到100的整数x和y,对x只能进行加1，减1，乘2操作，问最少对x进行几次操作能得到y？ 例如：a=3,b=11: 可以通过3*2*2-1，3次操作得到11；a=5,b=8：可以通过(5-1)*2，2
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摘要：题目描述 在一个字符串(0<=字符串长度<=10000，全部由字母组成)中找到第一个只出现一次的字符,并返回它的位置, 如果没有则返回 -1（需要区分大小写）. 在一个字符串(0<=字符串长度<=10000，全部由字母组成)中找到第一个只出现一次的字符,并返回它的位置, 如果没有则返回 -1（需要区
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摘要：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 betwe
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