Well, heck, if we're going to do this re-posting in a different
medium thing, here's what I had on FWP. Without benchmarking,
I put my money on it being faster.
#!/usr/bin/perl -w
use strict;
local $" = ',';
while (<DATA>) {
chomp;
my @chars = split //;
my $index = -1;
my %seen = ();
my $answer = [""];
while (++$index < @chars) {
if (exists $seen{$chars[$index]}) {
answer_set(\%seen, $answer);
$index = $seen{$chars[$index]};
%seen = ();
} else {
$seen{$chars[$index]} = $index;
}
}
answer_set(\%seen, $answer);
print "$_: @$answer\n";
}
sub answer_set {
my $seen = shift;
goto 'JUMP_' . ((keys %$seen <=> length $_[0][0]) + 1);
JUMP_0:
return;
JUMP_2:
$_[0] = [];
JUMP_1:
push @{$_[0]},
join "", sort { $seen->{$a} <=> $seen->{$b} } keys %$seen;
return;
}
__DATA__
mississippi
abcbef
adbcbef
that
abcdefa
abcdabc
testing
this test
abcdefg
-dlc