Re^2: scrambling all letters in a word until all combinations are found

Hi.

If you have the code available, I'd love to see the Perl code.

So what this is doing is..

@list contains the scrambled letters, ie: @list = (aesfght);

Then for each letter, we push it into @words following the next iterated letter. From here, I get kind of lost.

Thanks!

Comment on Re^2: scrambling all letters in a word until all combinations are found

Replies are listed 'Best First'.
Re^3: scrambling all letters in a word until all combinations are found by cmeyer (Pilgrim) on Feb 03, 2006 at 18:07 UTC
# takes an integer word length and a list of letters, # returns a list of words of the integer length # { my %cache; sub wordz { my ( $n, @letters ) = @_; my $cache_key = join( '', @letters, $n ); return if $n > @letters; return @letters if $n == 1; return @{ $cache{ $cache_key } } if exists $cache{ $cache_key }; my @wordz; for ( my $i = 0; $i <= $#letters; $i++ ) { push @wordz, map { $letters[ $i ] . $_ } wordz( $n - 1, @letters[ 0 .. $i - 1 ], @letters[ $i + 1 .. $#letters ] ); my @o = wordz( $n, @letters[ $i + 1 .. $#letters ] ); push @wordz, @o; } $cache{ $cache_key } = \@wordz; return @wordz; } } [download] It is also fun to do this problem non-recursively. If you are interested in that, I also have code (though there are different possible approaches). -Colin. WHITEPAGES.COM \| INC	[reply] [d/l]

Replies are listed 'Best First'.

Re^3: scrambling all letters in a word until all combinations are found
by cmeyer (Pilgrim) on Feb 03, 2006 at 18:07 UTC

# takes an integer word length and a list of letters,
# returns a list of words of the integer length
#
{ my %cache;
  sub wordz {
    my ( $n, @letters ) = @_;
    my $cache_key = join( '', @letters, $n );

    return if $n > @letters;
    return @letters if $n == 1;

    return @{ $cache{ $cache_key } } if exists $cache{ $cache_key };

    my @wordz;
    for ( my $i = 0; $i <= $#letters; $i++ ) {

      push @wordz, map { $letters[ $i ] . $_ }
        wordz( $n - 1, @letters[ 0 .. $i - 1 ],
                       @letters[ $i + 1 .. $#letters ] );

      my @o = wordz( $n, @letters[ $i + 1 .. $#letters ] );

      push @wordz, @o;
    }
    $cache{ $cache_key } = \@wordz;

    return @wordz;
  }
}
[download]

-Colin.

WHITEPAGES.COM | INC

[reply]
[d/l]