#!/usr/bin/env perl

use 5.010;
use strict;
use warnings;
use autodie;

die "Usage: $0 dictionary solution max_letters\n" unless @ARGV == 3;
my ($DICT, $SOLUTION, $MAX) = @ARGV;

my $count = 0;

open my $fh, '<', $DICT;
while (<$fh>) {
    s/%?\r?\n?$//;
    next if length > $MAX;

    if (matching_word($_)) {
        ++$count;
        say;
    }
}
close $fh;

say "Total: $count";

sub matching_word {
    state $solution_letters = [ split '' => $SOLUTION ];

    my ($word) = @_;

    foreach my $letter (@$solution_letters) {
        my $pos = index $word, $letter;

        if ($pos != -1) {
            substr($word, $pos, 1) = '';
            return 1 if length $word == 0;
        }
    }

    return 0;
}