Kubuntu 14.04 not getting updated

My Kubuntu 14.04 is not getting updated. When I am trying to update it shows as follows:-

" The package system is broken
Check if you are using third party repositories. If so disable them, since they are a common source of problems.
furthermore run the following command in a Terminal: apt-get install -f"

And the output of terminal as follows:

"biplab@biplab-desktop:~$ apt-get install -f
E: Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied)
E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?
biplab@biplab-desktop:~$ "

Please help, thanks - Biplab.