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in reply to Using regex to match double letters, and only double letters

Hi,

Using the above solution, you can also try the programs to find out the palindromes. For example,
 print $_ if ( $_ =~ /([[:alpha:]])([[:alpha:]])([[:alpha:]])([[:alpha:]])\3\2\1/i );
This above code matches of the palindrome of length 6.

In the same way you can apply your logic to find out the palindromes.

Hope this will enhance your view in regular expressions.

Regards,
S.Venni Rajan.
"A Flair For Excellence."
                -- BK Systems.

Replies are listed 'Best First'.
Re^2: Using regex to match double letters, and only double letters
by ysth (Canon) on Dec 30, 2005 at 10:29 UTC
    Lots of things you can do with backreferences. Even check for primes:
    perl -wle 'print "Prime" if (1 x shift) !~ /^1?$|^(11+?)\1+$/'
    (by Abigail)