linux apt-get modified source

1. cd / etc / apt /

2. cp sources.list sources.list.bak

3. sudo vi sources.list

4. Empty or comment out the previous

5. Paste the contents of what

Note # default image source to increase the speed apt update, if necessary, to cancel their own annotations 
the deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main Restricted Universe Multiverse 
# the deb the src-HTTPS: // Mirrors .tuna.tsinghua.edu.cn / Ubuntu / xenial main Tel Restricted Universe Multiverse 
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-the Updates main Tel Restricted Universe Multiverse 
# deb-src HTTPS: // Mirrors. xenial-the Updates main Tel Restricted tuna.tsinghua.edu.cn/ubuntu/ Universe Multiverse 
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial-backports main Tel Restricted Universe Multiverse 
# deb-src HTTPS: // Mirrors .tuna.tsinghua.edu.cn / Ubuntu / xenial-backports main Restricted Universe Multiverse 
the deb-Security main https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial Restricted Universe Multiverse
Deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial #-Security main Tel Restricted Universe Multiverse # pre-release software source is not recommended to enable # deb https://mirrors.tuna.tsinghua.edu .cn / Ubuntu / xenial Proposed main-Restricted Universe Multiverse # https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ the deb-xenial the src-Proposed main Restricted Universe Multiverse

6. sudo apt-get update

7. sudo apt-get upgrade

sudo apt-get install vim