ITPEC IP October 2021 Question 29
When character strings are searched by using wildcard characters, which of the following lists all and only the character strings that match the search expression “*A*.te??” among the character strings I through IV? Here, the wildcard character “?” represents any one (1) character and “*” represents a character string that consists of zero (0) or more of any characters.
Explanation
I only — A.text is the only string with an A somewhere before a literal ".te" that is followed by exactly two characters.
Read *A*.te?? piece by piece: any characters, an A, any characters, the literal characters .te, then exactly two characters. So a matching string ends in .te plus two characters and has an A before that .te.
Answer (a)
Why not others:
- •(b) I, II — treats
.texas enough, but each?must match exactly one character, so II is one character short - •(c) II, III, IV and (d) III, IV — III and IV contain "te", but not right after the dot; the dot in the pattern is a literal character and must stand directly before te
Key rule: * matches any number of characters including none, ? exactly one; every other character, the dot included, must appear literally and in that order.
Software · AI-written, may contain errors
This question comes from an official ITPEC past paper. ITPEC Practice is an independent study tool and is not affiliated with ITPEC. See the official IP past-paper collection or Report an issue.