#!/usr/bin/perl
use strict;

our @out;
our @data;

while (<DATA>) {
    chomp;
    push @data, $_ if ($_);
}

our $srtre  = qr/^(?:(\d+(?:\.\d+)*)?|\d*)(\D*)(.*)$/;

@out = sort {
    my $x = $a;
    my $y = $b;
    my $ret = 0;

    while (!($x eq $y)) {
        my ($xx, $yy);
        my ($l, $m, $xx, $yy);

        ($l, $xx, $x) = ($x =~ $srtre);
        ($m, $yy, $y) = ($y =~ $srtre);
        if ($l eq $m) {
# the common case
            if ($ret = $xx cmp $yy) {
                last;
            }
        } else {
            if (length($l) && length($m)) {
                if ($l =~ /\d+\.\d+\.d+/ || $m =~ /\d+\.\d+\.\d+/) {
                    my @ll = split(/\./, $l);
                    my @lm = split(/\./, $m);
                    if ($#ll == $#lm) {
                        for (my $x = 0; $x <= $#ll; $x++) {
                            if ($ret = ($ll[$x] <=> $lm[$x])) {
                                last;
                            }
                        }
                    } elsif ($#ll < $#lm) {
                        for (my $x = 0; $x <= $#ll; $x++) {
                            if ($ret = ($ll[$x] <=> $lm[$x])) {
                                last;
                            }
                        }
                        $ret = -1 unless ($ret);
                    } else {
                        for (my $x = 0; $x <= $#lm; $x++) {
                            if ($ret = ($ll[$x] <=> $lm[$x])) {
                                last;
                            }
                        }
                        $ret = 1 unless ($ret);
                    }
                    last if $ret;
                } elsif ($l == $m) {
# handle leading zeros.
# don't want (00 0 000)
                    if ($xx . $x eq $yy . $y) {
                        if ($ret = ($l cmp $m)) {
                            last;
                        }
                    }
                    if ($ret = ($xx cmp $yy)) {
                            last;
                    }
                } elsif ($ret = ($l <=> $m)) {
                    last;
                }
            } else {
                if ($ret = ($l.$xx cmp $m.$yy)) {
                    last;
                }
            }
        }
    }
    return $ret;
} @data;

print join(', ', @out), "\n";

__END__
a1.5
a1.5b
a1.55
a1.55b
a1.6
a1.6b
linux-2.4.3.tar
linux-2.4.28.tar
linux-2.4.29.tar
linux-2.4.29a.tar
linux-2.10.6.tar
linux-2.10.50.tar