Any chance of homework here? Probably not, looking at rest of OP history, but a good HW question.

--MidLifeXis

In reply to Re: REgular expression to check the string that allows "a","b" and "c" to occur only once in any order. by MidLifeXis
in thread REgular expression to check the string that allows "a","b" and "c" to occur only once in any order. by isha

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