The thief has found himself a new place for his thievery again. There is only one entrance to this area, called the “root.” Besides the root, each house has one...

Let f(n) be a sum of digits for positive integer n. If f(n) is one-digit number then it is a digital root for n and otherwise digital root of n is equal to digi...

Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.

Given a binary tree and a sum, find all root-to-leaf paths where each path’s sum equals the given sum.

x is guaranteed to be a non-negative integer.

早上到公司发现zabbix有一个报警：一台服务器的CPU使用率达到100%！ 1.立即登录该服务器查看CPU top10

由于是远程跟我沟通，我回复rac环境下可以重启一个节点，客户就自信重启了，出现的故障如下所示：

MySQL root用户不能为普通用户赋权限， 报错：Error Code: 1044. Access denied for user ‘root’@’%’ to database mysql> select host,user,password,Grant_priv,Super_priv FROM mysql.......

以上两个的区别是，第一个是在创建虚拟机的时候，就安装操作系统，第二个是安装完虚拟机之后再安装操作系统，我们使用第一种方式

Linux 下普通用户免密码切换 root 用户添加用户useradd [-g group] [-d user_home_directory] [-p “your password”] Username-g 表示设置新增用户所属用户组-d 表示设置新增用户的主目录-p 表示设置新增用户的登录...