# apt更新源
编辑/etc/apt/sources-list
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates main restricted
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial universe
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-updates universe
