剛安裝的Ubuntu18.10輸入 sudo apt-get install vim 安裝vim時出現如下問題：

[email protected]:~$ sudo apt-get install vim
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Package vim is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'vim' has no installation candidate

這個問題的原因是ubuntu的/etc/apt/source.list中的源比較舊了，需要更新一下，更新方法：

$ sudo apt-get update

更新完畢之後，再使用 sudo apt-get install vim 安裝應該就沒有問題了。

如果還有問題，就說明你的源有問題->

1.保險做法先備份原始檔：  cp -i /etc/apt/sources.list /etc/apt/sources.list_backup

2.開啟sources.list：   sudo gedit /etc/apt/sources.list   

3.在原始檔中複製貼上如下阿里雲的源到檔案的最前邊，然後儲存退出。

deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
deb http://archive.canonical.com/ubuntu xenial partner
deb-src http://archive.canonical.com/ubuntu xenial partner
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse

4.更新：sudo apt-get update

5.更新後，再安裝vim，sudo apt-get install vim

這次應該就沒有問題了。

如何修改源列表

http://wiki.ubuntu.org.cn/%E6%BA%90%E5%88%97%E8%A1%A8#Vivid.2815.04.29.E7.89.88.E6.9C.ACsudo%20gedit%20/etc/apt/sources.list

伺服器列表

http://wiki.ubuntu.org.cn/%E6%A8%A1%E6%9D%BF:18.04source