配置APT源

輸入命令 cd /etc/apt/ 進入改目錄後執行ls命令，會列出所以檔案目錄，把sources.list就是你要編輯配置的原始檔，先複製一份，然後重新編輯一份

然後就是刪掉sourceslist裡面所以的東西，換成下面的內容

deb http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse

deb http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse

deb http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse

deb http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse

deb http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse

deb-src http://mirrors.163.com/ubuntu/ trusty main restricted universe multiverse

deb-src http://mirrors.163.com/ubuntu/ trusty-security main restricted universe multiverse

deb-src http://mirrors.163.com/ubuntu/ trusty-updates main restricted universe multiverse

deb-src http://mirrors.163.com/ubuntu/ trusty-proposed main restricted universe multiverse

deb-src http://mirrors.163.com/ubuntu/ trusty-backports main restricted universe multiverse

儲存後，執行apt-get update命令，更新。