Regular Expressions (Linux+) Pattern Matching Quiz

1. In the pattern {2,5}, what does this quantifier specify?

Exactly 2 or 5 occurrences

Between 2 and 5 occurrences

At least 5 occurrences

Exactly 25 occurrences

2. What does the \b metacharacter represent?

Backspace character

Word boundary

Blank space

Beginning of pattern

3. Which pattern matches a phone number like 555-1234?

[0-9]{3}-[0-9]{4}

\d{3}-\d{4}

[0-9]+-[0-9]+

Both a and b

4. In sed, how do you reference a captured group in the replacement string?

$1, $2, etc.

\1, \2, etc.

&

Both a and b

5. What does the pattern .*? represent?

Any character, zero or more times (greedy)

Any character, zero or more times (non-greedy)

Any character, one or more times

Literal period followed by question mark

6. Which command uses regex to search files in Linux?

Ls

Grep

Cat

Mkdir

7. What does the $ metacharacter match?

The start of a line

The end of a line

A dollar sign

End of file marker

8. In grep, which flag enables extended regular expressions (ERE)?

-E

-r

-v

-i

9. Which regex matches an email-like pattern: user@domain.com?

^[a-z]+@[a-z]+\.[a-z]+$

[a-z]@[a-z].[a-z]

\w+@\w+\.\w+

Both a and c

10. What does \w match in a regular expression?

A whitespace character

A word character (letter, digit, underscore)

Any special character

A word boundary

11. What does the caret (^) metacharacter match in a regex pattern?

The start of a line

The end of a line

Any digit character

The literal caret symbol

12. What does [^abc] match?

The characters a, b, or c

Any character except a, b, or c

The start of a line

A negation symbol

13. Which pattern matches the literal dot character in regex?

.

\.

[.]

Both b and c

14. What does the pipe (|) symbol do in a regex pattern?

Matches literal pipe character

Provides alternation (OR)

Escapes the next character

Marks end of pattern

15. In regex, parentheses () are primarily used for:

Grouping and capturing

Escaping characters

Setting quantifier limits

Defining character classes

16. What does the pattern \s represent?

Any special character

A whitespace character

The letter 's'

A string delimiter

17. Which metacharacter matches zero or one occurrence of the preceding element?

*

+

?

|

18. What does \d match in a regular expression?

Any letter

Any digit (0-9)

A decimal point

A whitespace character

19. In the pattern [a-z], what does the hyphen represent?

Subtraction operation

A range of characters

Literal hyphen only

Word boundary

20. Which regex pattern matches one or more occurrences of the preceding element?

*

+

?

{1}

Regex Quiz: Can You Match the Pattern?

1. In the pattern {2,5}, what does this quantifier specify?

2.

What first name or nickname would you like us to use?

2. What does the \b metacharacter represent?

3. Which pattern matches a phone number like 555-1234?

4. In sed, how do you reference a captured group in the replacement string?

5. What does the pattern .*? represent?

6. Which command uses regex to search files in Linux?

7. What does the $ metacharacter match?

8. In grep, which flag enables extended regular expressions (ERE)?

9. Which regex matches an email-like pattern: user@domain.com?

10. What does \w match in a regular expression?

11. What does the caret (^) metacharacter match in a regex pattern?

12. What does [^abc] match?

13. Which pattern matches the literal dot character in regex?

14. What does the pipe (|) symbol do in a regex pattern?

15. In regex, parentheses () are primarily used for:

16. What does the pattern \s represent?

17. Which metacharacter matches zero or one occurrence of the preceding element?

18. What does \d match in a regular expression?

19. In the pattern [a-z], what does the hyphen represent?

20. Which regex pattern matches one or more occurrences of the preceding element?