Insert Delete GetRandom O(1)Design a data structure that supports all following operations in average O(1) time. insert(val): Inserts an item val to the set if not already present. remove(val): Remo
Game of LifeAccording to the Wikipedia’s article: “The Game of Life, also known simply as Life, is a cellular automaton devised by the British mathematician John Horton Conway in 1970.” Given a board
Find the Duplicate NumberGiven an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate number must exist. Assume that there is onl
Product of Array Except SelfGiven an array of n integers where n > 1, nums, return an array output such that output[i] is equal to the product of all the elements of nums except nums[i]. Solve it
Majority Element IIGiven an integer array of size n, find all elements that appear more than ⌊ n/3 ⌋ times. The algorithm should run in linear time and in O(1) space. 提示 解題應用 Array Array/Slice
Summary RangesGiven a sorted integer array without duplicates, return the summary of its ranges. For example:12345Given [0,1,2,4,5,7],return ["0->2","4->5","7"].
Combination Sum IIIFind all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Examp
Minimum Size Subarray SumGiven 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 one, return 0 instead. F
Two Sum II - Input array is sortedGiven an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number. The function twoSum should
Find Peak ElementA peak element is an element that is greater than its neighbors. Given an input array where num[i] ≠ num[i+1], find a peak element and return its index. The array may contain multipl
Maximum Product SubarrayFind the contiguous subarray within an array (containing at least one number) which has the largest product. For example:12Given the array [2,3,-2,4],the contiguous subarray [
Best Time to Buy and Sell Stock IISay you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete as many tran
Construct Binary Tree from Inorder and Postorder TraversalGiven inorder and postorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree.
Construct Binary Tree from Preorder and Inorder TraversalGiven preorder and inorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do not exist in the tree. 提
Subsets IIGiven a collection of integers that might contain duplicates, nums, return all possible subsets. Note: The solution set must not contain duplicate subsets. For example:If nums = [1,2,2], a
Search in Rotated Sorted Array II Follow up for “Search in Rotated Sorted Array”: What if duplicates are allowed? Would this affect the run-time complexity? How and why? Suppose an array sorted in a
Remove Duplicates from Sorted Array IIFollow up for “Remove Duplicates”:What if duplicates are allowed at most twice? For example:123Given sorted array nums = [1,1,1,2,2,3],Your function should retur
Word SearchGiven 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 “adjacent” cells are those horizontally or v
Sort ColorsGiven an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue. Here, we will use the
Search a 2D MatrixWrite an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted from left to right. The first i