Postgres 10 installation failing on Ubuntu 14

Hi,

I am trying to install postgres 10 on Ubuntu 14. I am already having
postgres 9.5.4 installed. I have followed the following steps for
installing postgres 10 -

sudo apt-get install software-properties-common python-software-properties
sudo add-apt-repository "deb http://apt.postgresql.org/pub/repos/apt/
trusty-pgdg main"
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc |
sudo apt-key add -
sudo apt-get update
sudo apt-get install postgresql-10

But it is failing with the below error

The complete installation log is attached.

invoke-rc.d: unknown initscript, /etc/init.d/postgresql not found.
dpkg: error processing package postgresql-10 (--configure):
subprocess installed post-installation script returned error exit status 100
Processing triggers for libc-bin (2.19-0ubuntu6.13) ...
Errors were encountered while processing:
postgresql-10
E: Sub-process /usr/bin/dpkg returned an error code (1)

Can someone let me know what is going wrong or how can I install postgres
10 on Ubuntu 14?