linux 找不到tree命令解决办法

今天用Ubuntu 发现有几个命令不能用，提示如下:

root@ubuntu:/# tree /home/

The program 'tree' is currently not installed. You can install it by typing:

apt install tree

然后找了找实际就是因为没有安装tree这个东西，执行安装

sudo apt-get install tree 

然后再执行命令如下:

root@ubuntu:/home# tree /home/

/home/

└── lhw

    ├── Desktop

    ├── Documents

    ├── Downloads

    │   └── sogoupinyin.deb

    ├── Music

    ├── Pictures

    ├── Public

    ├── Templates

    └── Videos

9 directories, 1 file