Resetting mysql root password in Ubuntu

After install mysql in Ubuntu, you should reset root password, those steps in below:
1.Stop Mysql, sudo /etc/init.d/mysql stop
2.sudo su
3.mysqld --skip-grant-tables &
4.After blank line, type mysql -u root mysql
5.UPDATE user SET Password=PASSWORD('XXXXXXXX') WHERE User='root';
6.exit
7.Stop Mysql, sudo /etc/init.d/mysql stop
8.exit su
Then, try new password with mysql -u root -p