error in sudo apt-get update

Dear users,

I am getting the following error,while updating sudo apt-get update
E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable)

E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?

So, 

I am unable to install octave ,g++, gfortran 

If any bady knows please help me

thank you