Apt-Get install in Ubuntu cannot install software 10

In ubuntu9.10, it is found that common software cannot be installed when the apt-Get install command is used, such as G ++. It seems that the log is too old for the source list, so on the website: http://ubuntu.srt.cn/find a group of source lists (9.10 is used if there is no 8.04 ):

deb http://ubuntu.srt.cn/ubuntu/ hardy main restricted universe multiversedeb http://ubuntu.srt.cn/ubuntu/ hardy-security main restricted universe multiversedeb http://ubuntu.srt.cn/ubuntu/ hardy-updates main restricted universe multiversedeb http://ubuntu.srt.cn/ubuntu/ hardy-proposed main restricted universe multiversedeb http://ubuntu.srt.cn/ubuntu/ hardy-backports main restricted universe multiversedeb-src http://ubuntu.srt.cn/ubuntu/ hardy main restricted universe multiversedeb-src http://ubuntu.srt.cn/ubuntu/ hardy-security main restricted universe multiversedeb-src http://ubuntu.srt.cn/ubuntu/ hardy-updates main restricted universe multiversedeb-src http://ubuntu.srt.cn/ubuntu/ hardy-proposed main restricted universe multiversedeb-src http://ubuntu.srt.cn/ubuntu/ hardy-backports main restricted universe multiverse

Run the command # sudo gedit/etc/APT/sources. List to open sources. List, delete all its contents, copy the top edge address, save and exit.
Run the command # sudo apt-Get update to update the source list.

In this way, you can install the software normally.