Is it a solvable problem to generate a regular expression that matches some input set?

Posted by Roman on Stack Overflow See other posts from Stack Overflow or by Roman
Published on 2010-12-21T09:59:48Z Indexed on 2010/12/21 11:54 UTC
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regex

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algorithm

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compiler-theory

I provide some input set which contains known separated number of text blocks.

I want to make a program that automatically generate 1 or more regular expressions each of which matches every text block in the input set.

I see some relatively easy ways to implement a brute-force search. But I'm not an expert in compilers theory. That's why I'm curious:

1) is this problem solvable? or there are some principle impossibility to make such algorithm?

2) is it possible to achieve polynomial complexity for this algorithm and avoid brute forcing?

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