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相关问题Discription 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:[ “((()))”, “(()())”, “(())()

相关问题Discription Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity.思路最小堆 该题为二路归并的变种，多路归并。使用最小堆结构在log(k)\log(k)时间复杂度内找到当前最小元素。时间复杂度：nlog(k)n\log(k) 空间复杂度

相关问题Discription 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 s

相关问题24. Swap Nodes in Pairs 25. Reverse Nodes in k-GroupDiscription Given a linked list, reverse the nodes of a linked list k at a time and return its modified list.k is a positive integer and is less

相关问题144. Binary Tree Preorder Traversal 94. Binary Tree Inorder Traversal 145. Binary Tree Postorder Traversal99. Recover Binary Search TreeDiscription Two elements of a binary search tree (BST) are

相关问题Discription Given s1, s2, s3, find whether s3 is formed by the interleaving of s1 and s2.For example, Given: s1 = “aabcc”, s2 = “dbbca”,When s3 = “aadbbcbcac”, return true. When s3 = “aadbbbacc

相关问题144. Binary Tree Preorder Traversal 94. Binary Tree Inorder Traversal 145. Binary Tree Postorder TraversalDiscription Given a binary tree, return the preorder traversal of its nodes’ values.For e

相关问题144. Binary Tree Preorder Traversal 94. Binary Tree Inorder Traversal 145. Binary Tree Postorder TraversalDiscription Given a binary tree, return the inorder traversal of its nodes’ values.For ex

相关问题144. Binary Tree Preorder Traversal 94. Binary Tree Inorder Traversal 145. Binary Tree Postorder TraversalDiscription Given a binary tree, return the postorder traversal of its nodes’ values.For

相关问题Discription Given n non-negative integers a1,a2,...,ana_1, a_2, ..., a_n, where each represents a point at coordinate (i,ai)(i, a_i). nn vertical lines are drawn such that the two endpoints of line

相关问题 11. Container With Most Water 42. Trapping Rain Water 407. Trapping Rain Water IIDiscription Given n non-negative integers representing an elevation map where the width of each bar is 1, compute

相关问题1. Two Sum 15. 3SumDiscription 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

Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution, and you may not us

Discription 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”,

相关问题17. Letter Combinations of a Phone Number 77. CombinationsDiscription Given a digit string, return all possible letter combinations that the number could represent.A mapping of digit to letters (j

相关问题1. Two Sum 15. 3Sum 16. 3Sum Closest 18. 4Sum 454. 4Sum IIDiscription Given four lists A, B, C, D of integer values, compute how many tuples (i, j, k, l) there are such that A[i] + B[j] + C[k]

Discription There 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)).Example 1: nums1 =

Discription 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.

Discription Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution, and you may not us

相关问题leetcode 46. PermutationsDiscription Given a collection of numbers that might contain duplicates, return all possible unique permutations.For example, [1,1,2] have the following unique permutation

Discription 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 means you have to modify the input 2D m

相关问题Discription Given a linked list, remove the n-th 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, t

Discription Given two integers n and k, return all possible combinations of k numbers out of 1 … n.For example, If n = 4 and k = 2, a solution is:[ [2,4], [3,4], [2,3], [1,2], [1,3],

Discription 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.For example, Given [3,2,1,5,6,4] and k = 2, ret

相关问题11. Container With Most Water 42. Trapping Rain Water 407. Trapping Rain Water IIDiscription Given an m x n matrix of positive integers representing the height of each unit cell in a 2D elevation