I uninstalled Postgres by following this question.
Now when I type sudo service postgresql status, it gives the following result
postgresql.service
Loaded: not-found (Reason: No such file or directory)
Active: inactive (dead)
Jan 15 12:02:37 induP systemd[1]: Starting PostgreSQL RDBMS...
Jan 15 12:02:37 induP systemd[1]: Started PostgreSQL RDBMS.
Jan 15 16:58:50 induP systemd[1]: Stopped PostgreSQL RDBMS.
Jan 15 16:58:57 induP systemd[1]: Stopped PostgreSQL RDBMS.
What is the problem?