node.js – 安装节点/运行npm install的问题

我正在尝试使用以下说明安装Node.js：

sudo apt-get update
sudo add-apt-repository ppa:chris-lea/node.js
sudo apt-get update
sudo apt-get install nodejs=0.10.18-1chl1~precise1

在这里找到：https://github.com/joyent/node/wiki/Installing-Node.js-via-package-manager

我运行这些命令,在最后一个命令后,我收到了这个错误：

Some packages Could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
diStribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may Help resolve the situation:

The following packages have unmet dependencies:
nodejs : Conflicts: npm
E: Unable to correct problems,you have Held broken packages.

我接下来尝试运行命令sudo apt-get install nodejs,这没有给我任何错误.

但是,当我运行“npm install”时,它无法显示：

npm ERR! install Couldn't read dependencies
npm ERR! Error: ENOENT,open '/home/Sarah/package.json'
npm ERR! If you need Help,you may report this log at:
npm ERR!     <http://github.com/isaacs/npm/issues>
npm ERR! or email it to:
npm ERR!     <npm-@googlegroups.com>

npm ERR! System Linux 3.8.0-30-generic
npm ERR! command "/usr/local/bin/node" "/usr/local/bin/npm" "install"
npm ERR! cwd /home/Sarah
npm ERR! node -v v0.11.8-pre
npm ERR! npm -v 1.3.11
npm ERR! path /home/Sarah/package.json
npm ERR! code ENOENT
npm ERR! errno -2
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /home/Sarah/npm-debug.log
npm ERR! not ok @R_964_6756@

谁能帮我弄清楚出了什么问题？
提前致谢