Pg version number format

PostgreSQL 9.3.1, compiled by Visual C++ build 1600, 32-bit

but I remember a 4 digit version numbering as

9.3.1-1

I can find this version convention used i.e. on http://www.ubuntuupdates.org/ppa/postgresql.

Is there a way to query pg for the full version number? I googled around but found only many off topic results.

I'm relatively new to pg admininistration so please excuse me if this is a dumb question.

Thanks in advance