摘要： 1. Array & List 1.1Sort Array的变更操作，好好运用尾指针：88题的end，75题的blueHead 88. Merge Sorted Array (Array) 75. Sort Colors 21. Merge Two Sorted Lists 23. Merge k 阅读全文

摘要： Given a binary tree, return the postorder traversal of its nodes' values. For example: Given binary tree {1,#,2,3}, return [3,2,1]. Note: Recursive so 阅读全文

摘要： Given a binary tree, return the preorder traversal of its nodes' values. For example:Given binary tree {1,#,2,3}, 1 \ 2 / 3return [1,2,3... 阅读全文

摘要： Given a binary tree, flatten it to a linked list in-place. For example, Given The flattened tree should look like: 法I：递归，前序遍历 法II：迭代 每次循环，找到左子树前序遍历的最后 阅读全文

摘要： Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations: get and set. get(key) - Get the 阅读全文

摘要： Given a linked list, return the node where the cycle begins. If there is no cycle, return null.Note: Do not modify the linked list. Follow up:Can you ... 阅读全文

摘要： Given a linked list, determine if it has a cycle in it. Follow up:Can you solve it without using extra space?思路：采用“快慢指针”查检查链表是否含有环。让一个指针一次走一步，另一个一次走两步... 阅读全文

摘要： Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Pan... 阅读全文

摘要： There are N children standing in a line. Each child is assigned a rating value. You are giving candies to these children subjected to the following re 阅读全文

摘要： Implement int sqrt(int x). Compute and return the square root of x. 注意: 计算平方的时候可能会溢出，所以mid要定义为long 另外，二分法初始上限不可能超过n/2+1 阅读全文

摘要： Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. 也可以通过引用传递，这样就不需要先初始化。 注意，NULL是一个宏定义 #def 阅读全文

摘要： Given an array where elements are sorted in ascending order, convert it to a height balanced BST.思路：使用二分法，将list的中间节点作为根节点，然后分别处理list左半边及右半边，以此递归。struc... 阅读全文

摘要： Given a sorted array of integers, find the starting and ending position of a given target value. Your algorithm's runtime complexity must be in the or 阅读全文

摘要： Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in or 阅读全文

摘要： Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list. For example,Given 1->2... 阅读全文

摘要： Given a sorted linked list, delete all duplicates such that each element appear only once. For example,Given 1->1->2, return 1->2.Given 1->1->2->3->3,... 阅读全文

摘要： Follow up for "Remove Duplicates": What if duplicates are allowed at most twice? For example, Given sorted array nums = [1,1,1,2,2,3], Your function s 阅读全文

摘要： Given a singly linked list L: L0→L1→…→Ln-1→Ln,reorder it to: L0→Ln→L1→Ln-1→L2→Ln-2→…You must do this in-place without altering the nodes' values.For ... 阅读全文

摘要： Given a list, rotate the list to the right by k places, where k is non-negative.For example:Given 1->2->3->4->5->NULL and k = 2,return 4->5->1->2->3->... 阅读全文

摘要： Reverse a linked list from position m to n. Do it in-place and in one-pass. For example: Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2 阅读全文