参见：https://www.cnblogs.com/york-hust/p/5438031.html 

hint：经常update一下，保证software source随时更新

#HUST

deb http://mirrors.hust.edu.cn/ubuntu/ xenial main restricted universe multiverse
deb http://mirrors.hust.edu.cn/ubuntu/ xenial-security main restricted universe multiverse
deb http://mirrors.hust.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse
deb http://mirrors.hust.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse
deb http://mirrors.hust.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://mirrors.hust.edu.cn/ubuntu/ xenial main restricted universe multiverse
deb-src http://mirrors.hust.edu.cn/ubuntu/ xenial-security main restricted universe multiverse
deb-src http://mirrors.hust.edu.cn/ubuntu/ xenial-updates main restricted universe multiverse
deb-src http://mirrors.hust.edu.cn/ubuntu/ xenial-proposed main restricted universe multiverse
deb-src http://mirrors.hust.edu.cn/ubuntu/ xenial-backports main restricted universe multiverse

#163

deb http://cn.archive.ubuntu.com/ubuntu/ xenial main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu/ xenial-security main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu/ xenial-updates main restricted universe multiverse
deb http://cn.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
##测试版源
deb http://cn.archive.ubuntu.com/ubuntu/ xenial-proposed main restricted universe multiverse
# 源码
deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial-security main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial-updates main restricted universe multiverse
deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
##测试版源
deb-src http://cn.archive.ubuntu.com/ubuntu/ xenial-proposed main restricted universe multiverse