After travelling hundreds of thousands of kilometers,Neil Armstrong stepped down onto moon marking the biggest milestone in human history.But strangely, after the first step, they din’t take much steps.The landing crew of the Apollo 11 lunar mission barely covered an area the size of a football field.Check out the below pic for the traverse map of the crew on moon surface.

Source: NASA history division website.

Many people are facing a common problem, where Orkut.com, Youtube.com and Firefox are blocked in their systems and they get following error with a scary laugh:

Orkut IS BANNED, orkut is banned you fool The administrators didnt write this program guess who did?? MUHAHAHA!!

So here is the procedure to solve this problem.

It happens bcoz of “Heap41a / win32.USBworm” which spreads through USB pen drives and removable storage devices. I’ll tell you manual method to remove the virus:

Follow these instructions:

1. Open “Task Manager” and goto “Processes” tab.

2. Look for services with name “svchost.exe“.

3. You’ll get approx. 2 services with the name “svchost.exe” which has your Windows username. End Task them.

4. Now open “regedit” from RUN and goto following keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Current Version\Run
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Current Version\Policies\Explorer\Run

If you find a key named “Winlogon” having value  “heap41a\svchost.exe” , delete it.

5. Now goto following key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Current Version\explorer\Advanced\Folder\Hidden\SHOWALL

Here change the key value of “CheckedValue” to 1

6. Now enable “Show Hidden Files/Folders” option in “Tools -> Folder Options” in My Computer.

7. Right-click on Start button and select “Open“. Now open “Programs” folder, here you’ll see a folder “Startup“. Open it and if you get a hidden file there, delete it. If its not there, then close it.

8. At last open “My Computer” and open C: drive.You’ll see a folder “heap41a” in C: drive. Delete it.

Thats it. After doing all this, restart your system and you’ll get rid of the virus.

In mid 2006, YouTube served approximately 100 million videos in a single day. To maintain a website of that scale, one would imagine YouTube has hundreds of DBAs. But in fact, there are just three people that make it all work. Paul Tuckfield, the MySQL DBA at YouTube shares horror stories about scalability at YouTube and how he coped with them to keep the show going everyday, while learning important lessons along the way.Follow the below link for video.

MySQL Conference & Expo - Paul Tuckfield

Above is a clip of US army blows up the swastika atop the Nazi Party rally grounds in Nuremberg which marked the end of Nazism and reign of Adolf Hitler, the Führer (Leader) of the Nazi party.

But I have been thinking and something doesn’t add up. Why did Hitler go through all that trouble to exterminate the Jewish people?No he was not lunatic.Then I don’t understand why go through such a huge operation to round up and destroy 6 million Jews in such a shortspan of time. No single reason seems to explain….

The dot-com bubble was a landslide event for software developers. You receive termination letter in your inbox or may be gazing at the calendar ,waiting for the call letters ,which never ever came. You simply cannot work in the field without having something miraculous or you are doomed.

The “dot-com bubble” was a speculative bubble covering roughly 1995–2001 during which stock markets in Western nations saw their value increase rapidly from growth in the new Internet sector and related fields. The period was marked by the founding (and in many cases, spectacular failure) of a group of new Internet-based companies commonly referred to as dot-coms. A combination of rapidly increasing stock prices, individual speculation in stocks, and widely available venture capital created an exuberant environment in which many of these businesses dismissed standard business models, focusing on increasing market share at the expense of the bottom line. The bursting of the dot-com bubble marked the beginning of a relatively mild yet rather lengthy early 2000s recession in the developed world.

 

Seven years later, are we heading for another dot-com bubble ? You might argue that the new bubble has been in effect since mid-2006, but the direction is absolute now. The job market for software developers is every bit boomed up as it was in 1999. Skyrocketing salaries resulting in beginners entering the software development field with giant dollar signs in their eyes. The signs are all around and I suggest better get prepared .I was too young for the first bubble , but I think this one gona be bigger!

Update:- Here Comes Another Bubble - The Richter Scales

*Click here if video not available in youtube!

Every one love it when Google crawlers index our site within minutes you publish new posts. But often there are cases in which you dont want to index some part of your web site. Reasons can be like,if you happen to have sensitive data on your site that you do not want the world to see. Or may be, if you have two versions of a page (one for viewing in the browser and one for printing), you’d rather have the printing version excluded from crawling, otherwise you risk being imposed a duplicate content penalty.

Robots.txt is a text file you put on your site to tell search robots which all pages you would like them not to visit. Let me make it clear, it’s no way a firewall or a kind of password protection but rather a request from ourside. Its up to the search engine to decide whether to accept it or not. May be like a “Please, do not enter” note on an unlocked door, you cannot prevent thieves from coming in but the good guys will not open to door and enter.But if ever you plan to implement this, do make it a point to place robot.txt in the main directory because they do not search the whole site for a file named robots.txt. Instead, they look in the main directory (http://XYZ.com/robots.txt) and if they don’t find it there, they simply assume that this site does not have a robots.txt. So, if you don’t put robots.txt in the right place, do not be surprised that search engines index your whole site.

I bet this happened with every one of you. You buy a brand new 100GB hard disk and happly after installation checks system manager to painfully realize that its shows 93GB in total. You get confused! Did the vendor cheated me?? or is it for some funky system usage they have reserved up my precious 7 GB?

You are not alone! The fact we finds out the hard way is that there are two ways to define a gigabyte!

When you buy a “100 Gigabyte” hard drive, the vendor defines it using the decimal powers of ten definition of the “Giga” prefix.

100 * 10⁹ bytes = 100,000,000,000 = 100 Gigabytes

But the operating system determines the size of the drive using the computer’s binary powers of two definition of the “Giga” prefix:

93 *  2³⁰  bytes = 99,857,989,632 = 93 Gigabytes

If you’re wondering where 7 Gigabytes of your 100 Gigabyte drive just disappeared to, you have the answers. It’s an old trick by hard drive makers– they intentionally use the official SI definitions of the Giga prefix so they can inflate the sizes of their hard drives, at least on paper. This was always an annoyance, but now it’s much more difficult to ignore, as it results in large discrepancies with today’s enormous hard drives. When your Terabyte hard drive is not a Terabyte? Its 931 GB.

Click the above pic to view the 200 most successful websites on the web this year, ordered by category, proximity, success, popularity and perspective in a single mindmap. Quite comprehensive and innovate method for data representation!

Operator overloading is one feature with c++ which has been induced with no real object oriented philosophy to support. But its one feature every java guys crave for. Why? The answer is obvious. Better readability and ‘makes-sense’. Let me clarify this point.

Lets assume2 objects of class type Point which need to add the corresponding x & y coordinated and returns a Point object

Lets try implement this with an Add( )member function
class Point
{
   int x;
   int y;
Public:
 Point add(Point  P1,Point P2);
};

So when ever you want to add two points this is what you will be doing and it works fine.

Point Result = varPoint.Add(Point1,Point2);

Now lets see how the same can be achieved using overloading The ‘+’ operator using operator overloading

class Point
{
   int x;
   int y;
Public:
 Point operator+ (Point & a, Point & b);
};

So when you want to add two points all you have to do is

Point PointResult = Point1 + Point2;

Now its up to you to interpret which style looks “normal” !!

Talking about operator overloading it will be of interest to imagine about following scenarios 

• Operator overloading functions as Friends
• Making operator overloading functions global

Now it smells nonsense, But its not!
You dig into any frame work classes you will find plenty of the above two species of operator over loaders. Which follows the next big question…WHY?

Consider the following C++ code: 

        class A {
                int x, y, z;
        public:
                A();
        };

        class B {
                A a;
        public:
                B() {}
        };

        A::A() {x = 0; y = 0; z = 0;}

Class A has a constructor A::A(), used to initialize three of the class’s data members. Class B has a constructor declared inline (defined in the body of the class declaration). The constructor is empty.

Suppose that we use a lot of B class objects in a program. Each object must be constructed, but we know that the constructor function body is empty. So will there be a performance issue?

The answer is possibly “yes”, because the constructor body really is NOT empty, but contains a call to A::A() to construct the A object that is part of the B class. Direct constructor calls are not used in C++, but conceptually we could think of B’s constructor as containing this code: 

        B::B() {a.A::A();}      // construct “a” object in B class

There’s nothing wrong about doing things; it falls directly out of the language definition. But in complex cases, such as ones involving multiple levels of inheritance, a seemingly empty constructor or destructor can in fact contain a large amount of processing.

You from India? Then this is going to be nostalgic. Following is a collection of old advertisements which used to come in our one and only national channel [im talking about late 80’s man!] Doordarshan. 

Talk about the latest pulsar 220cc leading the cc race for Bajaj….but not long before there was a time when good old Bajaj Chetek was the king…Do you remember the then Bajaj ad?…the one which gave an national integrity message….check it out below; for sure will pull up a smile on your  face…

And our very old Cadbury’s dairy milk ad…comes on guys now don’t say you forgot this cutie’s skirt….

This was a real horror…..you have spent lot of time forwarding this ad in your cassette player……..it’s the never ending Vicco turmeric ad….   This is very special for me. As a kid I loved this animated cartoon singing and playing around .The Public interest animated ad  ‘Ek Anek ‘.  

And here is the all time famous national integration ad ‘Mile Sur Mera Tumhara‘. It’s a class apart still now.

UPDATE:-

Giant Robot

Mile sur mera tumhara

The very first thought likely to hit will be that of taking mod 2(%2) of numbers from 1 to 100 in a loop and checking whether it yield an remainder or not. But there is even better a way to deal with it.

                 for( unsigned int i = 1; i < = 100; i++ )
                        if( i & 0×00000001 )
                                 cout << i<<” “;

The catch is, only odd number’s binary representation ends with ‘1’.Check the below table

Here in the below video Robert Scoble talks to Jeff Figueiredo, one of the senior search engine marketers at PointIt. Search-Engine-Marketers??? Yup, they are the one who buys millions of keywords from search engine giants Google-MSN-Yahoo for their billion dollar clients. Haven’t you noticed the Google ads coming up along with your Google search results? Who buys these search keywords for their company ads? Check out this new breed of advertisers chasing the keywords you type in your search boxes and the billions they hook up. Hear from him why Microsoft and yahoo struggle in competition with Google at search advertising arena. And he sum up saying….“There’s more dollars in play and Google is getting more of those dollars.”……sounds cooooooooooooooool.

A short 5 min video inside Google’s Mountainview office. Inspiring as always; this is a good watch. 

In this article I will be discussing one funny virtual function call.Consider the below code snippet:-

class V
{
      public:
      virtual void f() { }   //Virtual function
};
 
class A : virtual public V
{
      void f() { }           //NON Virtual function
};
 
class B : virtual public V
{
      void f() { }           //NON Virtual function
};
 
class D : public A, public B
{ };
 
int main()
{
  D d;
  V* vptr = &d;
  vptr->f();// which f(), A::f() or B::f()?    
}

When you try to compile the above code snippet you will get the following error dumps.

error C2250: ‘D’ : ambiguous inheritance of ‘A::A::f’
error C2250: ‘D’ : ambiguous inheritance of ‘B::B::f’

Let’s analyze this scenario a bit deeper. What I have done is I created a derived class (D) that inherits from two non virtual bases (A,B) that are derived from a virtual base class(V).

     V
    / \
  /     \
A        B
   \     /
     \ /
      D

In short its forms a deadly beautiful diamond with Class V at the top which has a Virtual function f() with two branches formed by class A and B. Both of these classes overrides the virtual function f().Do note that in class A and B the over ridden virtual functions are non virtual. Now Class D inherits class A and B. The issue is when f() is called by an object of D will it call the F() implemented by B(D::B::f)or the one implemented by C(D::C::f).Moral of the story - Never try this !

Related Reading:-

• Inside Virtual Functions
• Virtual Inline Functions
• Sister Class’s cross-delegation