On Jul 18, 11:33 am, [EMAIL PROTECTED] wrote: > Hi, > > Hi, > > I am taking a string as an input from the user and it should only > contain the chars:L , M or R > > I tried the folllowing in kodos but they are still not perfect: > > [^A-K,^N-Q,^S-Z,^0-9] > [L][M][R] > [LRM]?L?[LRM]? etc but they do not exactly meet what I need. > > For eg: LRLRLRLRLM is ok but LRLRLRNL is not as it has 'N' .like that. > > regards, > SZ > > The string may or may not have all the three chars.
With regular expressions, [^LRM] matches a character that isn't L, R or M. So: import re var = "LRLRLRLNR" if re.search(r'[^LRM]', var): print "Invalid" -- http://mail.python.org/mailman/listinfo/python-list