#! /usr/bin/perl
use strict;
use warnings;
use feature qw{ say };

use Data::Dumper;

use List::Util qw{ sum };
use Storable qw{ dclone };

my @list=('set abcde-efghi 12345',
          'set abcde-ijkl 12345',
          'clr abcde-efghi+123',
          'clr abcde-ijkl 12345');


my @divided = map [split //], @list;

sub score {
    my %freq;
    @freq{@$_} = () for @divided;
    my $score = (2 * keys %freq) + sum(map length, keys %freq);
    my $valid = ! grep 3 > length, keys %freq;
    return $score, $valid
}

sub concat {
    my @keys = @_;
    my $concat = join "", @keys;
    for my $d (@divided) {
        for my $i (1 .. $#$d) {
            splice @$d, $i - 1, 2, $concat
                if $d->[ $i - 1 ] eq $keys[0]
                && $d->[$i] eq $keys[1];
        }
    }
}

sub divide {
    my @keys = @_;
    my $concat = join "", @keys;
    for my $d (@divided) {
        for my $i (0 .. $#$d) {
            splice @$d, $i, 1, @keys
                if $d->[$i] eq $concat;
        }
    }
}

my $best = 'INF';
my $remember = dclone(\@divided);
my $count = 0;
while (1) {
    my ($score, $valid) = score();
    ++$count if $valid;
    last if $count > 2000;

    if ($score < $best && $valid) {
        $best = $score;
        $remember = dclone(\@divided);
    } elsif (! int rand 10) {
        @divided = @{ dclone($remember) };
    }
    if (int rand 4) {
        my $i = int rand @divided;
        my $j = int rand $#{ $divided[$i] };
        next unless @{ $divided[$i] } > 1;

        my @keys = @{ $divided[$i] }[$j, $j + 1];
        concat(@keys);
        my ($after) = score();
        divide(@keys) if $after > $score + int rand 3;

    } else {
        my $i = int rand @divided;
        my $j = int rand @{ $divided[$i] };
        my $l = 1 + int rand(length($divided[$i][$j]) - 1);
        next unless $l > 1;

        my @keys = (substr($divided[$i][$j], 0, $l),
                    substr($divided[$i][$j], $l));
        divide(@keys);
        my ($after) = score();
        concat(@keys) if $after > $score + int rand 3;
    }
}
say "Score $best";
print Dumper($remember);