Shell course summary

conditional
1. Judge whether there is a user's default on the current system shell by bash; If there is , It shows how many such users there are ; otherwise , It shows that there are no such users ;
2. Write a script Given a file , such as /etc/inittab Determine if there are blank lines in this file ; If there is , The number of blank lines is displayed ; otherwise , Show no blank lines .
3. Write a script Given a user , Judge it UID And GID Whether or not the same If the same , It shows that this user is “good guy”; otherwise , It shows that this user is “bad guy”、

Task a ：

Task 2 ：

Task three ：