PostgreSql in win32: postgres password

Using the installer with one click , two different things are created:

• Windows account and "service account" (which the postgresql.exe process belongs to)
• PostgreSQL ( )

() postgres. Windows net user:

net user            postgres
User name           postgres
Full name           postgres
Comment             PostgreSQL service account
...
Active              Yes
Password required   Yes
...

psql :

postgres=# \du
                       List of roles
 Role name |            Attributes             | Member of
-----------+-----------------------------------+-----------
 postgres  | Superuser, Create role, Create DB | {}

mayank ( mayank), (, PostgreSQL\version\bin PATH mayank):

cmd>initdb -U mayank -D C:\pgdata
cmd>pg_ctl -D C:\pgdata -o "-p 5440" -l C:\pgdata\log start
cmd>createdb -p 5440 test

, . C:\pgdata\pg_hba.conf :

# TYPE  DATABASE        USER            CIDR-ADDRESS            METHOD

# IPv4 local connections:
host    all             all             127.0.0.1/32            trust
# IPv6 local connections:
host    all             all             ::1/128                 trust

, . pg_ctl register postmaster Windows ( , 5432 DB), mayank " ".