My environment is a little different. I updated from 14.04 to 16.04 to 18.04.
My desktop PC 18.04 has npm installed.
$ npm -version
3.5.2
# nodejs -v
v8.10.0
# apt install npm
Reading package lists... Done
Building dependency tree
Reading state information... Done
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 to resolve the situation:
The following packages have unmet dependencies:
npm : Depends: node-gyp (>= 0.10.9) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
sudo apt-key add-
should besudo apt-key add -
with a little space afteradd
word. – Syed Abidur Rahman Oct 27 '18 at 18:20