Question

Which of the following statements is true?

a. Ranges of characters can be represented by placing a ~ between two characters.
b. [^Z] is the same as [A~Y].
c. Both A* and A+ will match AAA, but only A* will match an empty string.
d. All of above.

Answer 1

The correct answer is 'c. Both A* and A+ will match AAA, but only A* will match an empty string.' This statement refers to how regular expressions handle the quantifiers '*' and '+'. '*' matches zero or more occurrences, while '+' matches one or more occurrences.

Step-by-step explanation:

The question relates to regular expressions (regex), which are used in computing for pattern matching within strings. Among the options given, the statement that is true is:

c. Both A* and A+ will match AAA, but only A* will match an empty string.

Step-by-step explanation:

• A* matches zero or more occurrences of 'A', allowing it to match 'AAA' as well as an empty string.
• A+ matches one or more occurrences of 'A', which means it also matches 'AAA' but not an empty string.
• Option a is incorrect because ranges in regular expressions are usually represented with a hyphen ('-'), not a tilde ('~').
• Option b is not correct because [^Z] represents any character except 'Z', not the range from 'A' to 'Y' like [A-Y] does.