~Nacho/blog

Carlos shared a pretty cool link with me this morning. Codility is a platform to help recruiters and contractors to test developers before hiring them. Both the idea and the execution are beautiful. They’ve done a stunning job.

As part of my visit to the page I gave a try to the demo test. As it was funny to solve it, I’m sharing my solution here. The problem was quite easy. It reads like this:

Equilibrium index of a sequence is an index such that the sum of elements at lower indexes is equal to the sum of elements at higher indexes. For example, in a sequence A:

A[0]=-7 A[1]=1 A[2]=5 A[3]=2 A[4]=-4 A[5]=3 A[6]=0

3 is an equilibrium index, because:

A[0]+A[1]+A[2]=A[4]+A[5]+A[6]

6 is also an equilibrium index, because:

A[0]+A[1]+A[2]+A[3]+A[4]+A[5]=0

(sum of zero elements is zero) 7 is not an equilibrium index, because it is not a valid index of sequence A.

Assume the sum of zero elements is equal zero. Write a function int equi(int[] A); that given a sequence, returns its equilibrium index (any) or -1 if no equilibrium indexes exist. Assume that the sequence may be very long.

They gave me 30 minutes to design, code and test my solution. Here it is (tests omitted):

import operator
 
def equi(A):
  if A is None or len(A) == 0:
    return -1
  lsum = index = 0
  rsum = reduce(operator.add, A[1:], 0)
  while True:
    if lsum == rsum:
      return index
    index += 1
    if index == len(A):
      return -1
    else:
      lsum += A[index-1]
      rsum -= A[index]

It scores 100/100 and runs in linear time (that’s tricky because O(n²) algorithms will cause performance tests to fail) :)

I’ve lately spent some time developing a webapp for mobile devices to interact with some of the data published by the Gijón City Council. More specifically, data about local public land transportation schedule and live arrivals. The way they are presenting that information for mobile devices at the moment is very very heavy and slow, so I thought it may be useful to do something simpler for personal usage.

Basically, it is a simple web service that intensively caches data (to avoid stressing the data origin with many requests) and a fancy AJAX-powered frontend with some CSS with mobile browsers in mind (works flawlessly on Android’s browser and Mobile Safari). Additionally, if you add it as a bookmark to your iPhone’s home screen it behaves like a native application (you know, splash screen, custom icon, taskbar and so on).

I’m now working on client-side caching using HTML5 caching for offline usage. This way the application will boot way faster. It’s almost done, but it still needs some debugging.

I don’t intend to make it public for now. However, if you find it useful feel free to drop me a line. Beta testers are always welcome (but unfortunately won’t be rewarded).

This is how it looks like at the moment. The source will be released soon.

Update (23:26): Android screenshots provided by Javier Pozueco. Thanks buddy!

*lol*

Nowadays it’s very usual to find websites offering hints while you’re typing on a search box. Google is a pretty good example of it. But, how could it be implemented?

This feature could be implemented either in the client side or in the server side. If the word list is big (usually it is), it’s recommended to keep the lookup logic in the server side to save some bytes while transferring the page to the client and also to save some computing power using server-side caches (cool when you plan to serve many requests).

Either way, there should be a data structure somewhere containing the word list and an algorithm to do the lookup. The simplest approach may be to use a list to store the words and issue something like this when you want to get a list of hints for a given prefix:

filter(lambda x: x.startsWith(prefix), word_list)

That’s Python’s filter, but it works the same way the well-known Haskell’s first-order function filter does. It builds a new list with the elements of the original list (word_list) that match the predicate (the lambda function).

Although the results can (and should) be cached, the very first lookup (or when the cache expires) would be very inefficient because the entire list must be traversed and that operation will take linear time. Not bad, but when the size of the problem gets bigger (i.e. more and more words in the database) the lookup process may be too slow, especially whether you’re serving several users at the same time. If the list was sorted, the execution time could be improved a little bit by writing a more sophisticated algorithm, but let’s keep it that way for now.

Fortunately, there are better and faster ways to face the problem. If you don’t want to write code (usually the best choice) you may use some high-performance indexing engine such as Apache Lucene. But if you prefer the ‘do-it-yourself’ way (for learning purposes), a search tree (more specifically, a trie or a prefix tree) is a good approach.

I’ve poorly benchmarked both alternatives (the list and the tree) and as expected the tree is pretty quicker generating hints. What I did was to feed both data structures with the content of an American English word list holding ~640k words (debian package wamerican-insane).

So, assuming four is a reasonable minimum prefix length, I measured the time it would take to get a list of words prefixed by hous (yes, just one, remember I said this was a poor benchmark? ;). Unsurprisingly, it took around 230 times longer for the list alternative to generate the hints (438.96 ms vs 1.92 ms). Wow.

My implementation of the tree is as follows. The API is quite straightforward, the “hot” methods are put and get_hints. I’ve stripped off the test suite for space reasons.

Usage example:

>>> tree = HintSearchTree()
>>> tree.put("nacho")
>>> tree.put("nachos")
>>> tree.put("nachete")
>>> tree.get_hints("nach")
['nachete', 'nacho', 'nachos']
>>> tree.get_hints("nacho")
['nacho', 'nachos']
>>> tree.delete("nacho")
>>> tree.get_hints("nacho")
['nachos']
>>> tree.count_words()
2
>>> tree.get_hints("n")
['nachete', 'nachos']
>>> tree.is_indexed("nachete")
True
>>> tree.is_indexed("nach")
False
>>> tree.empty()
False

class HintSearchTreeNode(object):
class HintSearchTreeNode(object):
  def __init__(self, parent=None, terminal=False):
    self._children = {}
    self._terminal = terminal
    self._parent = parent
 
  @property
  def children(self):
    return self._children
 
  @property
  def terminal(self):
    return self._terminal
 
  @terminal.setter
  def terminal(self, value):
    self._terminal = value
 
  @property
  def parent(self):
    return self._parent
 
class HintSearchTree(object):
  def __init__(self):
    self._root = HintSearchTreeNode()
 
  def put(self, word):
    """Adds a word to the tree."""
    # TODO: Sanitize 'word'
    if len(word) > 0:
      self._put(self._root, word)
 
  def count_words(self):
    """Retrieves the number of indexed words in the tree."""
    return self._count_words(self._root)
 
  def is_indexed(self, word):
    """Returns True if 'word' is indexed."""
    node = self._find(self._root, word)
    return node is not None and node.terminal is True
 
  def get_hints(self, prefix):
    """Returns a list of words prefixed by 'prefix'."""
    return self._match_prefix(self._root, prefix)
 
  def delete(self, word):
    """Deletes 'word' (if exists) from the tree."""
    terminal = self._find(self._root, word)
    if terminal is not None:
      terminal.terminal = False
      self._prune(terminal.parent, word)
 
  def empty(self):
    """Returns True if the tree contains no elements."""
    return len(self._root.children) == 0
 
  def _put(self, node, word, depth=0):
    next_node = node.children.get(word[depth])
    if next_node is None:
      next_node = HintSearchTreeNode(parent=node)
      node.children[word[depth]] = next_node
    if len(word)-1 == depth:
      next_node.terminal = True
    else:
      self._put(next_node, word, depth+1)
 
  def _count_words(self, node):
    words = 1 if node.terminal is True else 0
    for k in node.children:
      words += self._count_words(node.children[k])
    return words
 
  def _match_prefix(self, node, prefix):
    terminal = self._find(node, prefix)
    if terminal is not None:
      return self._harvest_node(terminal, prefix)
    else:
      return []
 
  def _harvest_node(self, node, prefix, path=""):
    hints = []
    if node.terminal is True:
      hints.append(prefix + path)
    for k in node.children:
      hints.extend(self._harvest_node(node.children[k], prefix, path+k))
    return hints
 
  def _find(self, node, word, depth=0):
    if depth == len(word):
      return node
    else:
      child = node.children.get(word[depth])
      if child is not None:
        return self._find(child, word, depth+1)
      else:
        return None
 
  def _prune(self, node, word):
    if self._count_words(node.children[word[-1]]) == 0:
      del node.children[word[-1]]
      if len(node.children) == 0 and node.parent is not None \
          and node.terminal is not True:
        self._prune(node.parent, word[:-1])

The code is released in the public domain.

After almost a year without publishing a single post, it seems this week I’m going to beat all my records.

A week ago, I wanted to prank my brother for a while. Nothing sophisticated… just some Iptables rules, Tinyproxy and HTTP magic. To go ahead with my evil plans, I needed “something” able to redirect a HTTP request. Actually, there are several ways to do that: Apache redirects, Tornado, Netcat* and so on. These alternatives are fast, bulletproof and time-saving, but not fun.

As many of you probably know, I didn’t get a job yet. That necessary means that I’ve got plenty of free time to waste. So… what did I do? I wrote some Perl and today I’m publishing the source code just in case someone finds it useful somehow. Like the previous entry, it’s published in the public domain.

The script just collects connections, issues 301 back (Moved Permanently) and sets Location to the URI specified as a command line argument (option -u). It lacks some security checks (left as an exercise to the reader) but it does what it is supposed to do. You may likely spot some silly bugs as I haven’t spent much time reading it again. Reports are welcome!

For those wondering, the prank was a big success. I’m afraid I can’t spare any detail by now but it turns out my bro is still thinking that his computer has been cracked.

Example invocation:

$ perl redir.pl -p 7070 -v -t 3 -u http://31337.pl
2011/02/24 21:41:54 Listening on port 7070
2011/02/24 21:41:54 Redirecting HTTP requests to: ‘http://31337.pl’
2011/02/24 21:41:54 3 thread(s) working under the hood
…

And finally the source code:

use warnings;
use threads;
 
use Thread::Queue;
use POSIX;
 
use IO::Socket::INET;
use HTTP::Request;
use HTTP::Status qw(:constants status_message);
 
use Getopt::Long;
use DateTime::Format::HTTP;
use Data::Validate::URI qw(is_http_uri);
use Log::Log4perl qw(:easy);
 
use constant MAX_THREADS => 10;
use constant MAX_LEN_HEADERS_BUFFER => 8*1024;
use constant DEFAULT_REDIRECT_URI => "http://www.example.org";
use constant DEFAULT_PORT => 80;
use constant DEFAULT_POOL_SIZE => 3;
 
my $redir_uri = DEFAULT_REDIRECT_URI;
my $server_port = DEFAULT_PORT;
my $thread_pool_size = DEFAULT_POOL_SIZE;
my $verbose;
 
GetOptions('url=s' => \$redir_uri, 
           'port=i' => \$server_port,
           'threads=i' => \$thread_pool_size,
           'verbose'  => \$verbose) or exit -1;
 
die "Invalid redirect URI (e.g. http://www.example.org)\n" unless is_http_uri($redir_uri);
die "Invalid port (e.g. 8080)\n" unless 0 < $server_port && $server_port < 2**16;
die "Invalid pool size (should be in [1..".MAX_THREADS."])\n" 
            unless 0 < $thread_pool_size && $thread_pool_size <= MAX_THREADS;
 
Log::Log4perl->easy_init( level => $verbose? $DEBUG : $INFO );
 
my $pending = Thread::Queue->new(); 
 
my $lsock = IO::Socket::INET->new( LocalPort => $server_port,
                                   Proto => 'tcp',
                                   Listen => 1,
                                   Reuse => 1 ) or die "Couldn't bind listening socket ($!)\n"; 
 
INFO("Listening on port $server_port\n");
INFO("Redirecting HTTP requests to: '$redir_uri'\n");
 
my @workers = ();
for (1..$thread_pool_size) {
    if ($thread = threads->create("worker")) {
        push(@workers, $thread);
    }
}
 
DEBUG(sprintf("%d thread(s) working under the hood\n", $#workers+1));
 
# Set a tidy shutdown just in case an external agent SIG{INT,TERM}s the process
$SIG{'INT'} = $SIG{'TERM'} = sub {
    # Dirty hack. threads->kill() does not wake up the thread :(
    for (1..@workers) {
        $pending->enqueue(-1);
    }
    for (@workers) {
        DEBUG(sprintf("Worker %d terminated: %d clients served\n", $_->tid, $_->join())); 
    }
    close($lsock); 
    exit 0; 
};
 
while(1) {
    my $csock = $lsock->accept() or next;
    $pending->enqueue(POSIX::dup(fileno $csock));
    DEBUG(sprintf("New client enqueued: %s:%s\n", $csock->peerhost, $csock->peerport));
    close($csock);
}
 
sub worker {
    my $clients_served = 0;
    while(my $fd = $pending->dequeue) { # API promises thread safety :-)
        if ($fd == -1) {
            return $clients_served;
        }
 
        my $sock = IO::Socket::INET->new_from_fd($fd, "r+");
        DEBUG(sprintf("Dequeued client %s:%d by worker %d.\n", $sock->peerhost,
                            $sock->peerport, threads->tid()));
 
        my $buf = "";
        while(<$sock>) {
            # CAUTION: there isn't any self protection against very long lines
            last if /^\r\n$/;
            $buf .= $_;
            goto BYE if length $buf > MAX_LEN_HEADERS_BUFFER;
        }
 
        if (my $request = HTTP::Request->parse($buf)) {
            INFO(sprintf("[%s] %s {%s}\n", $request->method, $request->uri, $sock->peerhost));
        }
 
        printf $sock "HTTP/1.1 %d %s\r\n", 
            HTTP_MOVED_PERMANENTLY, status_message(HTTP_MOVED_PERMANENTLY);
        printf $sock "Date: %s\r\n", DateTime::Format::HTTP->format_datetime;
        print $sock "Location: $redir_uri\r\n";
        print $sock "Server: Simple HTTP Redirection/0.1 ($^O)\r\n";
        print $sock "Connection: close\r\n";
        print $sock "\r\n";
 
BYE:  
        $clients_served++;
        close($sock);
    }
}

(*) just an approach, may drop connections:

while [ 1 ]; 
 do echo -e "HTTP/1.1 301 Moved Permanently\r\nLocation: http://31337.pl\r\n\r\n" | nc -l 7070; 
done

This introduction is followed by some Python code (function evaluate_postfix_expr) to evaluate expressions (only integers, but may be extended with ease) in Reverse Polish Notation (RPN). Some simple tests are also included in the bundle.

I agree it’s a little useless, but I thought it might be useful for someone (CS students maybe?). If you want to examine the stack in each iteration you only have to turn debugging on. That can be accomplished by changing logging.INFO to logging.DEBUG (line 7).

Copy, distribute or do whatever you want with it. It’s released in the public domain.

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#!/usr/bin/env python
 
import logging
import re
import unittest
 
logging.basicConfig(level=logging.INFO)
 
operators_table = {'+': int.__add__, 
             '-': int.__sub__,
             '*': int.__mul__,
             '/': int.__div__,
             '^': int.__pow__}
 
class ExpressionError(Exception):
    def __init__(self, message):
        self._message = "Expression error: %s" % message
    def _get_message(self): 
        return self._message
    message = property(_get_message)
 
class TestEvaluation(unittest.TestCase):
    def test_correct(self):
        self.assertEqual(666, evaluate_postfix_expr("666"))
        self.assertEqual(2+3-6, evaluate_postfix_expr("2 3 + 6 -"))
        self.assertEqual(2*3+4, evaluate_postfix_expr("2 3 * 4 +"))
        self.assertEqual(2*(3+4), evaluate_postfix_expr("2 3 4 + *"))
        self.assertEqual(3**4, evaluate_postfix_expr("3   3  *     3  *      3 *"))
        self.assertEqual((7/2)**4, evaluate_postfix_expr("7 2 / 4 ^"))
        self.assertEqual((2**3)**4, evaluate_postfix_expr("2 3 ^ 4 ^"))
        self.assertEqual(5+((1+2)*4)-3, evaluate_postfix_expr("5 1 2 + 4 * 3 - +"))
 
    def test_malformed(self):
        self.assertRaises(ExpressionError, evaluate_postfix_expr, "+")
        self.assertRaises(ExpressionError, evaluate_postfix_expr, "2 +")
        self.assertRaises(ExpressionError, evaluate_postfix_expr, "+ 2 2")
        self.assertRaises(ExpressionError, evaluate_postfix_expr, "2 2")
        self.assertRaises(ExpressionError, evaluate_postfix_expr, "2 2 + -")
        self.assertRaises(ExpressionError, evaluate_postfix_expr, "a 2 -")
 
def evaluate_postfix_expr(expr):
    atoms = re.split(r"\s+", expr)
    stack = [] 
    for atom in atoms:
        if atom in ["+", "-", "*", "/", "^"]:
            try:
                op2 = stack.pop()
                op1 = stack.pop()
            except IndexError:
                raise ExpressionError("Too few operands (unbalanced)")
            logging.debug("Calculating %d %s %d" % (op1, atom, op2))
            atom = operators_table[atom](op1, op2)
        else:
            try:
                atom = int(atom)
            except ValueError:
                raise ExpressionError("Unable to parse '%s' as integer" % atom)
 
        try:
            stack.append(atom)
        except MemoryError:
            raise ExpressionError("Too long expression")
 
        logging.debug("Pushed element %d. Stack status: %s" % (atom, stack))
 
    if len(stack) == 1:
        return stack.pop()
    else:
        raise ExpressionError("Too many operands (unbalanced)")
 
if __name__ == "__main__":
    unittest.main()

Si Google te ha traído aquí, te resumo lo que pone a continuación: NO COMPRES EN DIESL.ES

Casi un año sin escribir en mi blog, principalmente por culpa del microblogging. Vamos allá.

Es rara la vez que compro cosas que no son de primera necesidad en tiendas tradicionales. Gracias a las oportunidades que Internet brinda al consumidor, es posible hoy en día hacerse con multitud de artículos a buen precio en tiendas en línea.

Para ser sinceros, no suelo comprar cosas en España. Acostumbro siempre a mercar en el Reino Unido, en Holanda (bromas aparte) o en los Estados Unidos. La calidad de los productos y el cumplimiento de los plazos de entrega es sencillamente impoluto. Por otro lado, la atención al cliente veloz e inteligente en la mayoría de los casos y la constante monitorización del estado del pedido hace que comprar en estas tiendas sea, en la mayoría de las ocasiones, una experiencia agradable. Pero, ¿qué pasa en España? Pues lo de siempre, aquí nos tomamos las cosas a pitorreo; el cliente: lo último de la lista. Os cuento.

Decidí comprar el martes pasado (30/03) un sintonizador TDT de alta definición. Lo quería para antes de la semana santa, por lo que necesitaba que el envío se realizara en, como mucho, 24 horas para que no se atragantara con las fiestas. Rebuscando por la Web, me encontré con la tienda online Diesl. Me venía como anillo al dedo, ya que en sus condiciones generales ponía (y pone a día de hoy) lo siguiente:

Para todos los pedidos a Península y Baleares los plazos de entrega serán de 24 horas, siempre que el pedido se realice antes de las 14:00 (hora española) y esté disponible en stock.

Perfecto, sólo necesitaba que hubiera stock del producto que quería.

Por si no se lee correctamente, decía claramente que el producto estaba disponible, y que el plazo de entrega era de 1 día.

Formalizo y pago el pedido el martes 30/03 a las 11:59. Qué bien, iba a tener al día siguiente antes de las 14:00 en mi casa el aparato, mis futboleros familiares iban a poder ver el partido de Champions League en TPA HD. El pedido pasó automáticamente al estado pagado. Además se dan prisa en cobrar, en mi cuenta corriente ya se reflejaba el pago.

Miércoles 31/03 12:00 (casi  24 horas después). El pedido sigue en el mismo estado y, por supuesto, a la dirección de entrega no ha llegado nada. Decido mandarles un correo a la dirección de contacto que aparece en la página, sección “Quienes somos“.

Vaya mala suerte:

Delivery to the following recipient failed permanently:

diesl en diesl punto com

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550 sorry, no mailbox here by that name. (#5.7.17)

Increíble, la única dirección de correo que encontré y no funciona.

Mirando en el correo electrónico de confirmación del pedido (más bien del pago, viendo lo visto), encuentro otra dirección de correo (tienda en diesl punto com) a la cual remito de nuevo mi correo, esta vez no hay rechazo.

Hola,

Ayer ordené y pagué inmediatamente el pedido número 1-888-LETS-GET-RETARDED (ficción publicitaria) en su tienda.

El producto adquirido rezaba como disponible y entregable en 1 día. Según sus “condiciones generales” si un producto está disponible y el pedido se hace antes de las 14h (como así fue hecho) el plazo de entrega es de 24 horas. En la página correspondiente a la información del pedido no hay constancia de que haya sido ni siquiera enviado. Por supuesto que el producto aún no lo he recibido en la dirección de entrega facilitada.

La única razón por la que decidí comprar en su tienda fue por el plazo de entrega, para evitar tener que esperar hasta la semana que viene (por las fiestas). Ruego si no son capaces de cumplir los  plazos de entrega cancelen el pedido

Esperando respuesta,

Y ya podía esperar, porque el correo lo mandé el 31/03 a las 14:34 y aún sigo esperando una respuesta a día de hoy.

El jueves 01/04 estuve fuera de casa y sin acceso a Internet. Cuando volví a mi domicilio el viernes por la tarde, el pedido había cambiado de estado: visto. Jajaja, ¿visto? ¡vaya bueno! ¿quién lo vió? por cierto, ¿mi correo lo vió alguien?

Pasan los días, hoy es 06/04 (es decir, ha pasado una semana) y sigue todo igual, en el mismo estado, el correo sin responder y yo sin mi compra (y sin mi dinero). A ver como acaba esta hazaña de comprar en España por Internet.

España, toros y olé. A tomar por el culo.

Actualización (06/04 @ 23:15): Les he mandado un nuevo correo, a distintas direcciones. Permutando los nombres diesl y tienda con los dominios diesl.es y diesl.com incluso utilizando la dirección de gmail asociada al registro del dominio, como sugería Pablete en los comentarios.

Actualización (07/04 @ 10:00): Sin respuesta, de momento.

Actualización (07/04 @ 12:15): Me llamaron por teléfono (¿no se darán cuenta de que si les mando un correo es porque quiero que me respondan por la misma vía?). Se disculpan achacando la culpa del retraso a un “fallo informático”. Joder, sin ánimo de desconfiar (o sí, ¡qué cojones! en el país de la picaresca y la mala fe como para no), pero esa excusa está alcanzando altos niveles de fama, ya es del calibre del “es que no sabía” o el “es que nadie me dijo que me habían dicho que mi jefe dijo que…”. El chaval muy majo, eso sí. Me aseguraron que mañana estará el producto en mi casa, con ocho días de retraso. Ver veremos. Sigo molesto de todos modos.

Esta semana comienzan las actividades conmemorativas del décimo aniversario de la AsturLiNUX.

Durante toda la semana hay programadas diversas actividades (charlas, talleres y conferencias) y como colofón, un gran acto central, el próximo sábado 18 de abril donde intervendrán Iván Frade (”Maemo; Software Libre Movil”) de Nokia y Rodrigo Salvador (”El Software Libre para la Gestión de la Red Educativa de la Junta de Andalucía”) de la Junta de Andalucía.

Además de estas ponencias, tendrá lugar una mesa redonda (“El Software Libre dentro y fuera de Asturias”) con una lista de participantes muy interesante.

Más información en la página principal y en el programa.

Doh! A new piece of software I couldn’t live without: Spotify.

1Password is a very powerful application for OSX to keep safe your passwords and identities. It works as a standalone application and as a series of plugins for several Internet browsers. It is capable of, among other things, autofill registration forms and save you a lot of time filling in the same personal information again and again. To autofill a login form, just click the 1P browser menu bar icon, choose a previously recorded identity and voila, 1Password logins in automagically with no further interaction.

All the harvested information is stored in a different keychain unlocked by a master key placed in the login keychain (See “Keychain access.app” for more information).

Macheist, in collaboration with Agile Web Solutions, is offering free licenses as a Christmas present here. You only have to create and account and click in the links below the tree to get your free license.

Yay! I’ve something cool to talk about.

It seems my brother is not very good with numbers and managed to block his SIM card by mistyping the PIN code three times in a row. The card is quite old, he inherited it from me time ago and God knows where the proper documentation which came along with it was. In short, we were screwed without the PUK code.

When the card was bought, there wasn’t any active law demanding mobile operators to establish any link between the card and its owner. Given that, I told him it will be hard to get the PUK to unlock the card because most likely the customer service would suspect the card was stolen and its new evil owner was trying to use it. Anyway, why don’t give it a try?

Dialing 1485…

Me: Hello. My cellphone is locked, it is asking for a code in order to get itself unlocked.

Op: What code? PIN code?

Me: Well, no. It requests the PUK code.

Op: I see. Is it a prepaid card?

Me: It is.

Op: Ok, turn off the device, remove the battery, extract the SIM card and tell me the numbers printed on it.

Me: Well… the numbers are: 11111111111111.

Op: Ok, and your phone number is…?

Me: 622222222.

Op: Ok. Your PUK is: 333333333333333.

Me: Thanks.

Op: Thanks for calling. Have a nice day.

Thus anyone who knows your telephone number and wants to read you messages, copy your contact list or call for free only has to steal your phone. You may now start worrying even if the phone was off, the security codes don’t protect your privacy at all.

I’ve finally committed the crime :)

I’ve been looking for a new monitor for a lot of time. Given I’ve decided to use my new Macbook as my unique desktop system it turned necessary to buy a new display to exploit in a better way the capacity of this marvelous operating system, MacOSX. 

Starting with the idea of buying a simple LCD 20″ monitor and after asking a bunch of anonymous multimedia and imaging amateurs for advice I ended up opening my scope and buying a gorgeous 23″ FullHD Dell display.

The monitor arrived today. Connecting it to my macbook through VGA was easy as pie, it looks incredibly stunning at 1920×1080. One of the main advantages of this display is its aspect ratio. Having an AR of 16:9 allows you to get rid of the annoying black parts on screen while watching 16:9 TV shows downloaded from the Internet. This way, you get an actual full screen :)

Take my advice and if you have in mind buying a new display evade old fashioned resolutions such as 1680×1050 and enjoy the FullHD experience.

I’ve also bought a wired Apple keyboard&mouse which have improved my desktop experience even more, having now a comfortable desktop setup to enjoy even more one of the things I do more often, spending uncountable hours in front of my beloved computer.

That’s all folks!

So Israel’s getting tense.
Wants one in self defense.
“The Lord’s our shepherd,” says the psalm,
But just in case, we better get a bomb.
Who’s next?

Mwhahaha!

Hahahahaha. Here.

I certainly love Boston Legal.