in reply to RegEx require

!/(.).*\1/

[download]

Replies are listed 'Best First'.
Re^2: RegEx require
by ikegami (Patriarch) on Nov 19, 2008 at 11:22 UTC
    It's probably faster just counting the digits 
    my %seen;
grep $seen{$_}++, /./g

    [download]
[reply]
[d/l]

In Section Seekers of Perl Wisdom