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Discussion of Problem 1559. TruCoders Linguistics

Can you explain this test?
Posted by Mickkie 12 Nov 2020 21:37
a0a*
F

My WA output N (infinite)
I interpret this as (a)concat(0)concat(a*) = {a, aa, aaa, aaaa, ...}
Re: Can you explain this test?
Posted by Markadiusz 5 Jul 2023 16:40
This expression describes words of the form xyz, where x comes from the set {a}, y comes from the set {} (i.e. empty set), and z comes from the set {empty_word, a, aa, aaa, ...}. Since y must be an element of an empty set, there is no such word of the form xyz, so the answer is F.