deb https://mirrors.ustc.edu.cn/ubuntu/ focal main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ focal main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ focal-updates main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ focal-updates main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ focal-backports main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ focal-backports main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ focal-security main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ focal-security main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ focal-proposed main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ focal-proposed main restricted universe multiverse
ubuntu22.04
deb https://mirrors.ustc.edu.cn/ubuntu/ jammy main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ jammy main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ jammy-updates main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ jammy-backports main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ jammy-security main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ jammy-security main restricted universe multiverse deb https://mirrors.ustc.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse deb-src https://mirrors.ustc.edu.cn/ubuntu/ jammy-proposed main restricted universe multiverse