11 2019 档案
摘要：Given two binary trees, write a function to check if they are the same or not. Two binary trees are considered the same if they are structurally ident
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摘要：Given a collection of intervals, merge all overlapping intervals. Example 1: Input: [[1,3],[2,6],[8,10],[15,18]] Output: [[1,6],[8,10],[15,18]] Explan
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摘要：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
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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: Input: [ [ 1, 2, 3 ], [ 4, 5, 6 ],
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摘要：Suppose you are at a party with n people (labeled from 0 to n - 1) and among them, there may exist one celebrity. The definition of a celebrity is tha
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摘要：You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: You have to rotate the image in-place, which
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摘要：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 endp
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摘要：Given an array nums of n integers where n > 1, return an array output such that output[i] is equal to the product of all the elements of nums except n
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摘要：Given an array of n positive integers and a positive integer s, find the minimal length of a contiguous subarray of which the sum ≥ s. If there isn't
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摘要：Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), find the minimum number of conference room
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摘要：Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],...] (si < ei), determine if a person could attend all mee
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摘要：Given a list of words and two words word1 and word2, return the shortest distance between these two words in the list. Example:Assume that words = ["p
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摘要：Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element. Example
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摘要：Implement atoi which converts a string to an integer. The function first discards as many whitespace characters as necessary until the first non-white
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摘要：Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library functio
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摘要：Given a non-empty array of digits representing a non-negative integer, plus one to the integer. The digits are stored such that the most significant d
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摘要：Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123 Output: 321 Example 2: Input: -123 Output: -321 Example 3: Input: 1
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摘要：Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring. Example 1: Input:
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摘要：Given a string array words, find the maximum value of length(word[i]) * length(word[j]) where the two words do not share common letters. You may assum
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摘要：Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array. Example 1: Input: [3,0,1] Output
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摘要：Write a function that takes an unsigned integer and return the number of '1' bits it has (also known as the Hamming weight). Example 1: Input: 0000000
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摘要：Given an integer, write a function to determine if it is a power of two. Example 1: Input: 1 Output: true Explanation: 20 = 1 Example 2: Input: 16 Out
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摘要：Given 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
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摘要：Given a non-empty array of integers, every element appears twice except for one. Find that single one. Note: Your algorithm should have a linear runti
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摘要：A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to determine if a number i
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摘要：Given a string s and a string t, check if s is subsequence of t. You may assume that there is only lower case English letters in both s and t. t is po
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摘要：Given two strings s and t , write a function to determine if t is an anagram of s. Example 1: Input: s = "anagram", t = "nagaram" Output: true Example
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摘要：Given a positive integer, return its corresponding column title as appear in an Excel sheet. For example: 1 -> A 2 -> B 3 -> C ... 26 -> Z 27 -> AA 28
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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：Compare two version numbers version1 and version2.If version1 > version2 return 1; if version1 < version2 return -1;otherwise return 0. You may assume
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摘要：Implement strStr(). Return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. Example 1: Input: haystac
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摘要：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.
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摘要：Given n non-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the hist
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摘要：Implement a basic calculator to evaluate a simple expression string. The expression string may contain open ( and closing parentheses ), the plus + or
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摘要：Given an encoded string, return its decoded string. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is be
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摘要：Given an absolute path for a file (Unix-style), simplify it. Or in other words, convert it to the canonical path. In a UNIX-style file system, a perio
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摘要：Implement the following operations of a stack using queues. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. to
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摘要：Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front
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摘要：Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) -- Push element x onto stack. pop() -- Remov
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