#!/usr/bin/perl -l
use strict;
use warnings;

my $i = '0' x @ARGV;

do {
  print join ',', map {substr($i, $_, 1)?$ARGV[$_]:()} 0..$#ARGV;
} while ($i =~ s/0(1*)$/"1"."0"x length("Å©")/e);

use strict;
use warnings;
use Data::Dumper;

my %pot=();

$"=';';
for(@ARGV){if(m#$"#){$".=int rand 10;redo}}# Damit der Inhalt von $" in keinem Element vorkommt

sub add
{
$pot{"@_"}=\@_;
for my $n(0..$#_){
my @n=@_;
splice @n,$n,1;
add(@n) unless exists $pot{"@n"}}
}

add(@ARGV);
$"=', ';# Für die Ausgabe wollen wir das schöner joinen
print "P(@ARGV) = {";
my $i=0;
for(values %pot){
  print ", " unless 0==$i++;
  print "{@$_}"}
print "}\n";

#!/usr/bin/perl

use strict;

# Eingabe
my @array = (1..9);

my %res;
warn time;
oneless(@array);
warn time;

# Formatierung der Ausgabe
# Key als Array umschreiben
my @res;
while(my($k) = each %res) {
    push @res, [split /,/, $k];
}
# Ergebnisarray schoener sortieren
@res = sort {
    my $r = @$a <=> @$b;
    if ($r == 0) {
        join(",", @$a) cmp join(",", @$b);
    } else {
        $r;
    }
} @res;
require Data::Dumper;
print Data::Dumper->new([\@res],['res'])->Indent(0)->Dump, "\n";

sub oneless {
    my @array = @_;
    $res{ join",",@array } = 1;
    return if !@array;
    for my $i (0 .. $#array) {
        oneless(map { $array[$_] } 0 .. $i-1, $i+1 .. $#array);
    }
}

print"(@x[grep{$i&1<<$_}0..$#x])
"while$i++<2**(@x=@ARGV)

print"(@x[grep{$i&1<<$_}0..@x])
"while$i++<2**(@x=@ARGV)'

print"{@a[grep$a&2**$_,0..@a]}"while$a++<2**(@a=@ARGV)

print"(@x[grep{$i&1<<$_}0..@x])
"while$i++<2**(@x=@ARGV)'

print"{@a[grep$a&2**$_,0..@a]}"while$a++<2**(@a=@ARGV)