Find out what/which words in your dictionary can be rearranged the most time to form other "valid" words. It makes one pass for every word in the file, plus one pass for every sorted word (join '', sort split //, $word). So if your dictionary contains no anagrams, it will take 2 passes through the entire dictionary. If every word has one anagram, two words per sorted word, it will take 1.5 passes through your dictionary. If every word has 3 anagrams, four words per sorted word, it will take 1.25 passes.

passes = (1/words-per-sorted-word) + 1

#!/usr/bin/perl -w

use strict;

use Getopt::Std;

my (%options);

getopts("d:h", \%options);

if ($options{h}) {
    print <<'eof';
    -d file: dictionary file
eof
exit;
}

my ($sorted_word, %word, @most_ref);

my ($number) = 0;

my ($word_file) = $options{d} || "/usr/share/dict/words";

open(WORDS_FH, "<" . $word_file) or die ("Can't open $word_file: $!\n"
+);

while (<WORDS_FH>) {
    chomp;
    $sorted_word = join '', sort split //, $_;
    push @{$word{length($sorted_word)}{$sorted_word}}, $_;
}

foreach my $length (keys %word) {
    foreach $sorted_word (keys %{$word{$length}}) {
        if ($number < $#{$word{$length}{$sorted_word}}+1) {  
            $number = $#{$word{$length}{$sorted_word}}+1;
            @most_ref=();
            push @most_ref, \@{$word{$length}{$sorted_word}};
        } elsif ($number == $#{$word{$length}{$sorted_word}}+1) { 
            push @most_ref, \@{$word{$length}{$sorted_word}};
        }
    }
}

print $number . ":\n";
foreach my $word_ref (@most_ref) {
    foreach my $word (sort @{$word_ref}) {
        print " " x 2 . $word . "\n";
    }
    print "\n";
}
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#!/usr/bin/perl -w

use strict;

use Getopt::Std;

my (%options);

getopts("d:h", \%options);

if ($options{h}) {
    print <<'eof';
    -d file: dictionary file
eof
exit;
}

my ($sorted_word, %word, @most_ref);

my ($number) = 0;

my ($word_file) = $options{d} || "/usr/share/dict/words";

open(WORDS_FH, "<" . $word_file) or die ("Can't open $word_file: $!\n"
+);

while (<WORDS_FH>) {
    chomp;
    $sorted_word = join '', sort split //, $_;
    push @{$word{$sorted_word}}, $_;
}

foreach $sorted_word (keys %word) {
    if ($number < $#{$word{$sorted_word}}+1) {  
        $number = $#{$word{$sorted_word}}+1;
        @most_ref=();
        push @most_ref, \@{$word{$sorted_word}};
    } elsif ($number == $#{$word{$sorted_word}}+1) { 
        push @most_ref, \@{$word{$sorted_word}};
    }
}

print $number . ":\n";
foreach my $word_ref (@most_ref) {
    foreach my $word (sort @{$word_ref}) {
        print " " x 2 . $word . "\n";
    }
    print "\n";
}
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