Word deconstruction finder

startling.pl

#!/usr/bin/perl
use Data::Dumper;
use strict;

my $len;
my %tree;
while(<>) {
    chomp;
    if(/^[A-Za-z]+$/) {
        $tree{length($_)}{$_} = [];
    }
}
#Lots of weird single letters in my dicts...
$tree{1} = {
    'a' => [],
    'i' => [],
};

my @lengths = sort {$b <=> $a} keys %tree;
for my $length (@lengths) {
    print "$length letters: " . scalar(keys %{$tree{$length}}) . "\n";
}

print check_word('startling');
die();
my $curlen = shift @lengths;
my @coolwords;
while(scalar(@coolwords) < 1) {
    for my $word (keys %{$tree{$curlen}}) {
        print "Checking $word...\n";
        if(check_word($word, $len, 0)) {
            push(@coolwords, $word);
        }
    }
}
print @coolwords;

sub check_word($$$) {
    my $word = shift;
    my $len = shift;
    my $depth = shift;
    if(!$len) { $len = length($word); }
    if(exists $tree{$len}{$word}) {
        if($len == 1) {
            return 1;
        } else {
            my $continues = 0;
            for(my $whichletter = 0; $whichletter < $len; $whichletter++) {
                my $subword = substr($word, 0, $whichletter) . substr($word, $whichletter+1);
                if(check_word($subword, $len-1, $depth+1)) {
                    print " "x$depth . "$word -> $subword\n";
                    push @{$tree{$len-1}{$subword}}, $word;
                    $continues = 1;
                }
            }
            return $continues;
        }
    } else {
        return 0;
    }
}