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  1. Is every language with a finite number of strings regular?
  2. Is the language of all strings regular?

I am new to this topic and got confused. Can any one please help me with this?

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    $\begingroup$ These are, in fact, the most trivial examples of regular languages (empty language aside) and you should find them in any book on the subject. $\endgroup$ – Karolis Juodelė Feb 14 '13 at 15:36
  • $\begingroup$ @abc13 A.Schulz answered the question, you should mark is as answered. $\endgroup$ – mrk Feb 14 '13 at 17:52
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  1. Yes. Assume the language is $L=\{w_1,w_2,\ldots, w_n\}$. then you can form the regular expression $w_1 + w_2 + \cdots + w_n$, which describes $L$.

    You can also argue with finite automata or regular grammars.

  2. Yes, if your alphabet is $\Sigma=(a_1,\ldots,a_k)$ then the regular expression $(a_1+a_2+\cdots +a_k)^*$ describes the languages of all possible strings over $\Sigma$.

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