如何在UBUNTU 13.10上安装R？如果我使用apt-get，则找不到包：
sudo apt-get install r-base r-base-dev
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package r-base
E: Unable to locate package r-base-dev
或：
sudo apt-get install r-base-core
Reading package lists... Error!
E: Malformed line 57 in source list /etc/apt/sources.list (dist)
E: The list of sources could not be read.
E: The package lists or status file could not be parsed or opened.