摘要：
Given a binary tree, flatten it to a linked list in-place. For example, given the following tree: The flattened tree should look like: 给一个二叉树，把它展平为链表 阅读全文
摘要：
Given m arrays, and each array is sorted in ascending order. Now you can pick up two integers from two different arrays (each array picks one) and cal 阅读全文
摘要：
In social network like Facebook or Twitter, people send friend requests and accept others' requests as well. Table request_accepted holds the data of 阅读全文
摘要：
In social network like Facebook or Twitter, people send friend requests and accept others’ requests as well. Now given two tables as below: Table: fri 阅读全文
摘要：
Select all employee's name and bonus whose bonus is < 1000. Table:Employee Table: Bonus Example ouput: 选出所有奖金<1000元的雇员姓名及奖金数额 解法1： 解法2： All LeetCode Q 阅读全文
摘要：
The Employee table holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id. Given the Em 阅读全文