# DFA that accepts word and its reverse [duplicate]

The problem is as follows: design DFA over an alphabet {a,b}, that accepts a language: L = {$$xwx^R$$ | $$x \in \{a,b\}^+, w \in \{a,b\}^+$$}

I have no idea how to remember the first word to be able to detect a reverse of it. I will appreciate any help.

• Okay, I found the solution. We have to assume that $w \in \{a,b\}$ so we have to only check if first and the last letter is the same. – PatrykTraveler Jan 26 '19 at 0:49
• @Apass.Jack While some reputation is required to close questions, you can always try to flag your own post, requesting closure so that it ends up in the close votes queue. (While flagging everywhere requires 15 rep, flagging on (comments on) your own post can be done by everyone) – Discrete lizard Jan 26 '19 at 11:20