Given two binary trees, write a function to check if they are equal or not. Two binary trees are considered equal if they are structurally identical and the nodes have the same value. 递归遍历左子树和右子树 /*** Definition for a binary tree node.* struct T…
转自 21分钟 MySQL 入门教程 一、MySQL的相关概念介绍二、Windows下MySQL的配置配置步骤MySQL服务的启动、停止与卸载三、MySQL脚本的基本组成四、MySQL中的数据类型五、使用MySQL数据库登录到MySQL创建一个数据库选择所要操作的数据库创建数据库表六、操作MySQL数据库向表中插…
计数信号量用来控制同时访问某个特定资源的操作数或同时执行某个指定操作的数量 A counting semaphore.Conceptually, a semaphore maintains a set of permits. Each acquire blocks if necessary until a permit is available, and then takes it. Each release adds a permi…