Maria DB not starting

Maria DB not starting. Job for mariadb.service failed. See 'systemctl status mariadb.service' and 'journalctl -xn' for details

[root@localhost ~]# systemctl restart mariadb.service

Job for mariadb.service failed because the control process exited with error code. See "systemctl status mariadb.service" and "journalctl -xe" for details.

ok 

STEP 1.

[root@localhost lib]# yum remove mariadb-server

STEP 2.

[root@localhost lib]# rm -rf /var/lib/mysql

STEP 3.

[root@localhost lib]# yum install mariadb-server

STEP 4.

[root@localhost lib]# systemctl start mariadb.service

[root@localhost lib]# mysql -u root -p