The snippet uses Math::Combinatorics module. Given a set of characters as an array. It returns all the possible combinations of the characters ranging from 1 character to total size of the array.

Update: Data::Dumper included. Thanks to zentara.
#!/usr/bin/perl -w
use strict;
use Data::Dumper;

my @n = ('A' .. 'C');
my @all_string = get_char_comb(@n);

print "There are: ",scalar(@all_string)," strings\n";
print Dumper \@all_string;

sub get_char_comb
{
    use Math::Combinatorics;

    my @alph = @_;
    my @all;

    foreach ( 0 .. $#alph+1  )
    {
        my $combinat = Math::Combinatorics->new( count => $_,
                                                 data => [@alph],
                                                );

        while(my @permu = $combinat->next_combination)
        {
            push @all, join("",@permu);
        }

    }
        return @all;
}

[download]
Output: 
$VAR1 = [
          'A',
          'B',
          'C',
          'AB',
          'AC',
          'BC',
          'ABC'
        ];

[download]

In reply to Characters Combinations of All Sizes by monkfan

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.