#!perl

use warnings;
use strict;
use Benchmark qw(timethese);

our(@all, @sorted, @results);

for my $dir ("/bin/", "/usr/bin/") {

        my $D;
        opendir $D, $dir;
        @all = readdir $D;
        closedir $D;
        chdir $dir;
        print "$dir contains ".@all." files\n";

sub sort_ord {
        @sorted = sort { -s $a <=> -s $b } @all;
}
sub sort_sch {
        @results =
                map $_->[0],
                sort { $a->[1] <=> $b->[1] }
                map [$_, -s $_],
                @all;
}
sub sort_new {
        my %h;
        @h{@all} = map {-s $_} @all;
        @results = sort { $h{$a}<=>$h{$b} } @all;
}
sub cmp_them {
        join("\n", @sorted) eq join("\n", @results) or
                die "bad sort";
}

        sort_ord;
        sort_sch; cmp_them;
        sort_new; cmp_them;

timethese -5, {
        Ordinary => \&sort_ord,
        Schwartzian => \&sort_sch,
        Strange => \&sort_new,
        };

}