IINN DDEE XX

Science and Technology

1. War of Cyberworlds ................................................................................... 8

2. Computer Viruses ...................................................................................... 10

3. One Tonne Baby – The Begining of Modern Computers ........................... 13

4. The Science of Sleep .................................................................................. 15

General Articles

5. Inter Service Selection Boards ................................................................... 18

6. Urban to Urban .......................................................................................... 20

Poetry and Humour

7. My Computer ............................................................................................ 22

8. Twinkle Twinkle ......................................................................................... 23

9. Smile Please ............................................................................... ................ 24

Puzzles – Quizzes – Challenges

10. Test Yourself! ............................................................................................. 26

11. Logical Puzzles ........................................................................................... 27

12. Sudoku ....................................................................................................... 28

13. Programming Challenges ........................................................................... 29

Learning and Information

14. Learning C++ .............................................................................................. 31

15. Explore With Me ........................................................................................ 35

16. Tips n Tricks ............................................................................................... 36

17. Software of the Month .............................................................................. 37

18. Usefull Links ............................................................................................... 38

19. The Constituion ......................................................................................... 39

20. MAG News ................................................................................................. 40

TThhee HHoollyy QQuurraann TT rraa nnss ll aa tt ii oo nn oo ff

MMoo nn tt hh ll yy SS ee rr ii ee ss

[2:1] Alif-Laam-Meem. (Alphabets of the Arabic language; Allah and to whomever He reveals, know their

precise meanings.)

[2:2] This is the exalted Book (the Qur’an), in which there is no place for doubt; a guidance for the pious.

[2:3] Those who believe without seeing (the hidden), and keep the (obligatory) prayer established, and

spend in Our cause from what We have bestowed upon them.

[2:4] And who believe in this (Qur’an) which has been sent down upon you, O beloved Prophet,

(Muhammed - peace and blessings be upon him) and what was sent down before you; and are certain of the

Hereafter.

[2:5] It is they who are on guidance from their Lord; and they are the successful.

[2:6] As for those whose fate is disbelie f, whether you warn them or do not warn them - it is all one for

them; they will not believe. (Because their hearts are sealed - see next verse).

[2:7] Allah has sealed their hearts and their ears, and on their eyes is a covering; and for them is a terrible

punishment.

AL

- B

AQ

RA

H S

ec

tio

n - 1

HHaaddiitthh

[ Sahi Bukhari Volume 1, Book 2, Number 27 ]

[ Sahi Bukhari Volume 1, Book 2, Number 38 ]

[ Sahi Bukhari Volume 1, Book 2, Number 40]

Narrated 'Abdullah bin 'Amr:

A person asked Allah's Apostle . "What (sort of) deeds in

or (what qualities of) Islam are good?" He replied, "To

feed (the poor) and greet those whom you know and

those whom you don't know."

Narrated Abu Huraira:

The Prophet said, "Religion is very easy and whoever

overburdens himself in his religion will not be able to

continue in that way. So you should not be extremists, but

try to be near to perfection and receive the good tidings that

you will be rewarded; and gain strength by worshipping in

the mornings, the nights."

Narrated Abu Huraira:

Allah's Apostle said, "If any one of you improve (follows

strictly) his Islamic religion then his good deeds will be

rewarded ten times to seven hundred times for each good

deed and a bad deed will be recorded as it is."

EE-- MM

AAGG

TTEE A

AMM

EEddiittoorr-- iinn--cchheeiiff

Mian Zeshan Farooqi

EEddiittoorr

Naveed Hamid

CCoo--eeddiittoorr

Ayesha Naeem Mirza

CCoouunnsseell iinngg OOff ffiicceerr

Dilawer Hussain

AAddvveerrtt iissoorr

Mobeen Afzal

RReeppoorrtteerr

Majid Ali

On the way of success…

The first edition of E-MAG was published on

March 1s t, 2009. By the grace of Allah Almighty we

got excellent response from everywhere. Our

teachers, fellows and other readers made us able

to continue publishing E-MAG by encouraging us

and providing us with their valuable feedbacks.

We’ve tried to bring betterments in this edition, in

the light of your suggestions. We’re pleased to

announce that E-MAG is going to publish ‘TWO

BIG SERIES’. One big series was started from the

first edition i.e. Translation of The Holy Quran. The

second BIG SERIES, we’re going to start from this

edition is The Constitution of Pakistan (1973)

Moreover we’re inviting more people to articles

for E-MAG and show off their talent to the world.

Students from different universities and colleges

are showing their interest in writing for this

magazine. We welcome all of you to participate in

E-MAG.

As I said before that your feedbacks are really

important for us. It was the encouragement and

suggestions of people which made us able to

continue this work. Therefore we request you to

please keep on providing us your feedbacks and

suggestions so that we can do better!

Thanks

Editor-in-chief

“In the name of Allah Almighty, the

most beneficent, the most merciful"

EEDDIITTOORRIIAALL

First of all, I would like to congratulate my teachers, colleagues and other

students who showed great interest in the E-MAG and without their

contribution it would be impossible to publish the second edition.

Secondly, I am glad to inform you that the first edition of E-MAG was

successfully published and both the teachers and students appreciated our

effort. In the first edition more than 1000 download were a result of the

quality articles submitted by the students. We also received valuable

feedbacks from the teachers and students as well. We have published their

feedbacks in this edition.

The second edition has been published. In the beginning we used free

hosting but as the number of downloads increased the free quota ended

and readers had to wait for a day so now, we have started our own website

so that there is no downloading problem. You can download your free

copy/copies whenever you want without waiting.

The feedback has helped us a lot in improving the stuff of the mag. We

have included the sections which you suggested in your feedbacks. But as

some of the suggestions were not practical so we have excluded them such

as political and religious articles because as it were a bit controversial.

The second edition covers the articles related to science, technology,

general discussion, stories, challenges, quizzes, puzzles and much more on

the same pattern as in the first edition but with different and wider scope.

I hope you will like the second edition as well. Keep us providing with

your valuable feedbacks.

Editor

Cyberspace is the global domain of electro-

magnetics accessed through electronic

technology and exploited through the

modulation of electromagnetic energy to

achieve a wide range of communication and

control system capabilities. Cyberworlds are

information worlds formed on cyberspace. (Wikipedia)

WWaarr ooff CCyybbeerrwwoorrllddss Written by: Faiza Raana

Forget about James Bond. There is a better, faster, nastier and cleverer spy than you might have ever imagined of: cyberspy.

Curiously, these virtual superspies can make life utterly uglier for our pure-flesh-and-bone spies -- put on super-payrolls --

working round the clock world wide – the CIA, MI6, Mossad – you name it.

This sort of cyber-warfare is hardly a new thing though. When Russians were accused of a cyber-attack on Estonia a couple of

years ago, it came about as a wake-up call for the White House airing concern that America was vulnerable to similar

warfare. And when some in the military sparked suspicion that Chinese cyber spies had already sneaked into unclassified

Pentagon computers, cyber crafts considered starting a chain of cyber command to fight for America's supre macy online.

The $2 billion project, kick-started under the wing of the USAF, was due to

become fully operational later. Ominous adverts about hack attacks on the

Pentagon were commissioned to recruit more men and women. And then, it

was suspended. No reason was given. The notion that modern countries

should consider cyberspace a theatre of war is a no-brainer. It seems like they

have had a lot of political maneuverings over who should run it in the first

place. The question is hardly whether there should be one, but where.

That is barely the only question the USAF Cyber Command had to answer.

People were scarcely sure whether it was there to protect air force assets or

all cyberspaces. Some thought it would only be responsible for computer

networks, while others were convinced that anything that used the electromagnetic spectrum would fall under its purview --

including laser weapons. And no one knows why it was put in charge of both cyberspace and space operations.

Cyber Command came to life in response to millions of attack probes or scans from malicious computers on the Department

of Defence's Global Information Grid (or GIG), encompassing the military's networks, systems

and computers. Evidently, the nature of the threat is large and diverse. It includes recreational

hackers, self-styled cyber-vigilantes and various groups with nationalistic or ideological

agendas, trans-national actors and nation-states. The need for that came when the Pentagon

felt a new section was must because much of the Department of Defence's networks, systems

and computers depend on commercial telecom links and the Internet.

Cyber Command is there to take any military actions in cyberspace. Blowing things up, making them not work, just like in the

real world. It is also offensive and defensive, just like in the real world. But the consequences could be catastrophic too:

potential costs of a multi-critical infrastructure attack on the banking system, the power grid and so on in a sequence

designed to do maximum damage approaches the trillions, and the damage would look like a thousand hurricane Katrinas.

E - M A G

8 Central air conditioners use 98% more energy than ceiling fan.

It is scarcely something a 14-year old could do in his bedroom, however. You would need half a billion dollars and three

years. But that amount of money and time is hardly an absolute barrier to entry -- nation states or trans-national terror gangs

like al Qaeda or even someone like the Russian Mafia, which is not terrorism but organized crime, could certainly pile up that

kind of money.

Several cyber crafts claim Cyber Command is a step in the right direction – up or down it is anybody’s guess: they want to

treat cyberspace as an area for war like a physical space, which is exactly the way to look at it. So is the suspension of Cy ber

Command going to make America more vulnerable? It is hard to answer though many think having someone in charge and

capable of handling the mission is needed urgently.

Many heap blame on political chicanery in the USAF. After scandals about botched

handling of nukes, major contracts going wrong and the firing of the top military and

civilian leaders, the service needs time to regroup before deciding on how to contest

in the cyber arena. But when and if it does come back online, there are still questions

to be answered.

Cyber Command has the right to monitor anything that comes across its own networks, for defence purposes, and there is

hardly any evidence it is going beyond that. Some cyber company titans are worried about how rigorously the American

government will maintain the line between military surveillance and civilian prosecutions.

That sheer scare stems from the army being unable to do the policing duty because there are laws against that, and the USAF

should then hardly be able to check up on civilian cybercrime. The needs of warfare are scarcely the same as the needs of

peacetime -- we barely need howitzers, Predators and B-2 Stealth bombers in peacetime, and we barely need Cyber

Command monitoring us either. Does not the war on terror justify it? They are lying if they say that. They can pretend it is the

same as war, but it is not. The war on terror is just a rhetorical war.

Do you know about Moore’s Law?

The co-founder of Intel Inc. Gordon Moore stated in 1965 that:

“The numbers of transistors incorporate

in a chip will approximately double every

24 Months”

This statement is known as Moore’s Law.

E - M A G

9 In Australia, a dust-devil is called a "willy-willy."

Gordon Moore

CCoommppuutteerr VViirruusseess Written by: Naveed Hamid

Computer viruses is a term which we daily hear in our life but only few of us actually have a technical knowledge about how these

viruses work. This article will definitely help you a lot in understanding what actually a computer virus is and how does it work. A

computer virus is a program which attaches itself to another program to have a drastic effect and it affects software or hardware or

both. This is a definition which we normally hear from our teachers or formally written in the text books but actually a comp uter virus is

an intelligent program which directly communicates with hardware or operating system.

The familiar and well known computer viruses are :

Boot sector viruses

Companion viruses

Email viruses

Logic bombs and time bombs

Macro viruses

Cross-site scripting virus

I will not discuss what do they viruses do and which hardware components and soft wares are being affected because you can find their

details easily in any available text books.

Early history

The first computer virus was written by Rich Skrenta in 1982, and it was named “Elk Cloner” and was spread by floppy disk. The first PC

virus was a boot sector virus written in 1996 by two brothers Basit and Amjad Farooq Alvi operating out of Lahore, Pakistan. Since the

mid 1990’s macros viruses have become common. These viruses are written in scripting languages for Microsoft programs such as Word

and Excel.

Types of computer viruses

Computer viruses broadly classifies in to two categories. One is the “nonresident viruses” and the other is “resident viruses ”.

Nonresident Viruses

A nonresident virus searches for other hosts that can be infected, infect those programs, and then transfers control of that program that

it infected (Britannica). The nonresident viruses consist of two major parts. First one is the ‘fi nder module’ and second one is the

‘replicator module’. The finder module finds the host files to be infected and on finding the host files it calls the replica tor module to

infect those files. For simple virus the replicator’s tasks are:

1. Open the new file

2. Check if the executable file has already been infected (if it is, return to the finder module)

E - M A G

10 It takes eight and a half minutes for light to get from the sun to earth

3. Append the virus code to the executable file

4. Save the executable's starting point

5. Change the executable's starting point so that it points to the start location of the newly copied virus code

6. Save the old start location to the virus in a way so that the virus branches to that location right after its execution.

7. Save the changes to the executable file

8. Close the infected file

9. Return to the finder so that it can find new files for the replicator to infect.

Resident Viruses

Contrary to the nonresident virus a resident virus doesn’t search for programs to infect when its started, it instead loads itself into the

memory when its executed and then transfers control to the host program. The virus then stays active and infects new hosts w hen

those files are accessed (Britannica).

From here resident viruses can be divided into to types of programs, fast infectors and slow infectors. Fast infectors are designed to

contaminate as many files as possible. This specific type of virus can wreak havoc on a virus scanner. If the virus scanner fails to detect

the infected file, that virus can follow the scanner and then infect all the following files that are scanned. The disadvant age relative to

the virus in this case is that infecting that many more files makes it easier to detect, and then subsequently repair (Britannica). Slow

infectors are designed to infect hosts infrequently such as when they are copied. They are designed this way to avoid detect ion by virus

scanners by limiting their actions. Though these specific viruses are harder to detect, they are not as commonly used as fast infectors

using the mentality of infecting as many files as quickly as possible (Britannica).

From here some viruses take action to avoid detection. Some viruses use stealth software by hiding itself until a virus scanner has

passed its file thus seeming that the file is clean and from there infecting the operating system. Other viruses have self -modification

code that, once detected by a scanner, can modify itself and change, allowing the user to delete the infected file but having the modified

virus still on the computer (Britannica).

Other viruses have different code structures and employ them to deter detection by virus scanners. One such code is “polymorphic”

code which infects files with an encrypted copy of itself, which is then decoded by a decryption module (HowStuffWorks). Wit h these

viruses the decryption module is adjusted after each infection making a well written “polymorphic” virus extremely difficult to detect

since it has no parts that stay the same. Another code is “metamorphic” code which rewrites itself completely each time it i nfects a new

program. A “metamorphic” code is usually very large and complex making its detection also extremely difficult (Britannica).

Computer viruses can be broken down into several different types of infections. As stated before a virus is a small software program

that “piggybacks” on real programs. Other types of viruses are e-mail viruses, moving around through e-mail messages and duplicating

itself by automatically mailing itself to several of the people in the victim’s address book. Worms are also a small software program that

uses computer networks such as a business/corporation or a college campus to spread. It scans that network for other machines that

have specific security holes. It copies itself to the new machine using that security hole, and starts to duplicate from the re as well.

Another type of infection is a Trojan horse which is a computer program that claims to do one thing but does another when you run it.

Trojan horses however have no way of duplicating automatically (HowStuffWorks).

E - M A G

11 The United States Mint once considered producing donut-shaped coins.

It’s important to understand that all viruses aren’t initially damaging or destructive to your computer while some are merely annoying,

with the virus being a simple pop up. Other viruses however can erase programs and delete memory. Some of these programs don’t act

immediately and have a delayed payload and can be triggered to be set off like a bomb on a specific day, wait till it has infected a certain

amount of hosts, or until a specific program is run. However once that action is taken the virus is implemented, completing its program

whether that be a small annoying pop up or erasing your entire hard drive (Britannica).

Some people create viruses with negative intentions to harm others. Their purpose is to damage their valuable data and information

while other people create viruses just for the sake of learning. Their purpose is to find bugs in the soft wares and operatin g system so

that these bugs can be removed. Some people claim as computer viruses only harm so they should not be created but for the academic

purposes it is the best way of learning the computer hardware and software and I think that courses related to virus designin g must be

offered in the universities so that students have a better understanding of the technology.

IILLOOVVEEYYOOUU

E - M A G

12 There are approximately 90 people that have been frozen after their death.

ILOVEYOU was a computer virus that hit numerous computers in

2000, when it was sent as an attachment to an email message

with the text "ILOVEYOU" in the subject line. The virus arrived in

e-mail boxes on May 4, 2000, with the simple subject of

"ILOVEYOU" and an attachment "LOVE-LETTER-FOR-

YOU.TXT.vbs". Upon opening the attachment, the virus sent a

copy of itself to everyone in the user's address list, posing as the

user. It also made a number of malicious changes to the user's

system. It caused loss of billion dollars to the world. (Wikipedia)

Replica of SSEM at Museum of Science and Industry at

Manchester

OOnnee TToonn BBaabbyy The Beginning Of Modern Computers

Do you know when the history of computer began? Everyone would answer this question differently. One may say that history of

computer begins from 300-BC with Abacus. This argument might be correct if you define computer as ‘a machine which counts

something’.

Many people consider the Charles Babbage’s Analytical Engine as the beginning of computer history. Babbage’s Analytical Engine was

not a physical machine. It was just an idea of first general-purpose-computer presented by Babbage in 1837. Babbage kept on working

on this design till his death in 1871. After his death, the progress in the field of computer was very slow even almost ended at a time. But

the proverb ‘Necessity is the mother of Invention’ proved when World War II started.

Many programmable computers were built during 1940s decade. Some of them were built to meet the needs of military during the war

while some were later on built with the aim of progress. UK built Colossus and USA built ENIAC. Both ENIAC and Colossus were

programmable computers. ENIAC was built to calculate the trajectory of shells for the US army while Colossus was built to decrypt

messages from the German High Command during World War II. Both ENIAC and Colossus were

reprogrammable but this could take a very long time, even several days, to reprogram these

computers.

On June 21st, 1948 just after 11:00am, the world’s first electronic digital programmable computer

executed its first program successfully at Manchester University. This computer is known as

Manchester Small-Scale Experimental Machine (SSEM) and sometimes as Mark-I Prototype. As it was

the first electronic digital programmable computer with memory storage and it was the beginning of

modern computers so it was nicknamed as ‘The Baby’. It was built at the Victoria University of

Manchester by Frederic C. Williams, Tom Kilburn and Geoff Tootill .

The key feature The Baby was its memory. Cathode Ray Tubes (CRTs) were used to store a program.

A metal grid was attached to the screen to read the different charges. A graphical representation - dashes for a one and dots for a zero -

was displayed on a second CRT wired in parallel to the memory device. Input to the Baby was by setting sequences of bits at chosen

addresses using a simple keyboard. Output was by reading the information on the

Display Tube. The Baby had 32-bits word length and storage of 32 words

(extendable up to 8192). It had a single address format order code and it could

perform serial binary arithmetic operation using 2s complement i.e. it could

perform only one arithmetic operation that is subtraction. It was 5.2 meters long,

2.2 meters high and weighs one tonne! It occupied a whole room. Today’s

calculators are tiny but work much more efficient than The Baby.

The Baby had an instruction set of three bits i.e. it could perform maximum 23 = 8

instructions but it had only 7 instructions:

E - M A G

13 Japan uses the most energy per year than any other country.

A page from Geoff Tootill's notebook

shows a program wri tten for Baby. All

the data and programs had to be

wri tten in 1024 bits

Freddie Williams

Tim Kilburn

Instruction Set of The Baby (SSEM)

Binary code Modern mnemonic Operation

000 JMP S Jump to the instruction at the specified memory address (absolute

unconditional jump}

100 JRP S Jump to the instruction at the specified memory address plus the number

specified (relative unconditional jump)

10 LDN S Take the number from the specified memory address, negate it, and load it

into the accumulator

110 STO S Store the number in the accumulator at the specified memory address

001 or 101* SUB S Subtract the number at the specified memory address from the value in

accumulator, and store the result in the accumulator

11 CMP Skip next instruction if the accumulator contains a negative value

111 STP Stop

*The function bits were only partially decoded, to save on logic elements

The first program was written by Tim Kilburn (one of the creators of The Baby). This program was

consisted of 17 instructions and so far as can be ascertained first ran on 21 June 1948. It was designed

to find the highest proper factor of 218 (262,144) by trying every integer from 218 − 1 downwards. The

divisions were implemented by doing repeated subtractions of the divisor. The SSEM took 3.5 million

operations and 52 minutes to produce the answer (131,072). The program used eight words of working

storage in addition to its 17 words of instructions, giving a program size of 25 words. Geoff Tootill wrote

an amended version of the program the following month, and in mid-July Alan Turing—who had been

appointed as a reader in the mathematics de partment at Manchester University in September 1948—

submitted another program, to carry out long division.

The Baby morphed into the Manchester Mark I and eventually the first commercial general purpose

computer, the Ferranti Mark I. In 1998, a working replica of The Baby, now on display at the Museum of

Science and Industry in Manchester, was built to celebrate the 50th anniversary of the running of its first

program. Demonstrations of the machine in operation are held regularly at the museum.

References: BBC, Wikipedia, University of Manchester

Do you know?

E - M A G

14 Research indicates that plants grow healthier when they are stroked.

The world's largest semiconductor company and

the inventor of x86 series of microprocessors,

Intel, was founded on July 18, 1968 Robert

Noyce and Gordon Moore.

Written by: Mian Zeshan Farooqi

TThh ee SSccii eenn ccee ooff SS ll ee eepp

Why do we sleep?

So why do we sleep? This is a question that has baffled scientists for centuries and the answer is, no one is really sure.

Some believe that sleep gives the body a chance to recuperate from the day's activities but in reality, the amount of

energy saved by sleeping for even eight hours is miniscule - about 50 kCal, the same amount of energy in a piece of

toast.

We have to sleep because it is essential to maintaining normal levels of cognitive skills such as speech, memory,

innovative and flexible thinking. In other words, sleep plays a significant role in brain development.

What would happen if we didn't sleep?

A good way to understand the role of sleep is to look at what would happen if we didn't sleep. Lack of sleep has serious

effects on our brain's ability to function. If you've ever pulled an all -nighter, you'll be familiar with the following after-

effects: grumpiness, grogginess, irritability and forgetfulness. After just one night without sleep, concentration

becomes more difficult and attention span shortens considerably.

With continued lack of sufficient sleep, the part of the brain that controls languag e,

memory, planning and sense of time is severely affected, practically shutting down. In

fact, 17 hours of sustained wakefulness leads to a decrease in performance equivalent to

a blood alcohol level of 0.05% (two glasses of wine). This is the legal drink driving limit in

the UK.

Research also shows that sleep-deprived individuals often have difficulty in responding to rapidly changing situations

and making rational judgements. In real life situations, the consequences are grave and lack of sleep is said t o have

been be a contributory factor to a number of international disasters such as Exxon Valdez, Chernobyl, Three Mile Island

and the Challenger shuttle explosion.

Sleep deprivation not only has a major impact on cognitive functioning but also on emotiona l and physical health.

Disorders such as sleep apnoea which result in excessive daytime sleepiness have been linked to s tress and high blood

pressure. Research has also suggested that sleep loss may increase the risk of obesity because chemicals and hormon es

that play a key role in controlling appetite and weight gain are released during sleep.

What happens when we sleep?

What happens every time we get a bit of shut eye? Sleep occurs in a recurring cycle of 90 to 110 minutes and is divided

into two categories : non-REM (which is further split into four stages) and REM sleep.

E - M A G

15 In the United States, the most frequent month for a tornado to occur is in May.

Non-REM sleep

Stage one: Light Sleep

During the first stage of sleep, we're half awake and half asleep. Our muscle activity slows down and slight twitching

may occur. This is a period of light sleep, meaning we can be awakened easily at this

stage.

Stage two: True Sleep

Within ten minutes of light sleep, we enter stage two, which lasts around 20

minutes. The breathing pattern and heart rate start to slow down. This period

accounts for the largest part of human sleep.

Stages three and four: Deep Sleep

During stage three, the brain begins to produce delta waves, a type of wave that is large (high amplitude) and slow

(low frequency). Breathing and heart rate are at their lowest levels.

Stage four is characterised by rhythmic breathing and l imited muscle activity. If we are awakened during deep sleep we

do not adjust immediately and often feel groggy and disoriented for several minutes after waking up. Some children

experience bed-wetting, night terrors, or sleepwalking during this stage.

REM sleep

The firs t rapid eye movement (REM) period usually begins about 70 to 90 minutes after we fall asleep. We have around

three to five REM episodes a night.

Although we are not conscious, the brain is very active - often more so than when we are awake. This is the period

when most dreams occur. Our eyes dart around (hence the name), our breathing rate and blood pressure rise.

However, our bodies are effectively paralysed, said to be nature's way of preventing us from acting out our dreams.

After REM sleep, the whole cycle begins again.

How much sleep is required?

There is no set amount of time that everyone nee ds to sleep, since it varies from person to person. Results from the

sleep profiler indicate that people like to sleep anywhere between 5 and 11 hours, with the average being 7.75 hours.

Jim Horne from Loughborough University's Sleep Research Centre has a simple answer though: "The amount of sleep

we require is what we need not to be sleepy in the daytime."

Even animals require varied amounts of sleep:

E - M A G

16 The speed of sound must be exceeded to produce a sonic boom.

Species Average total sleep time per day

Python 18 hrs

Tiger 15.8 hrs

Cat 12.1 hrs

Chimpanzee 9.7 hrs

Sheep 3.8 hrs

African elephant 3.3 hrs

Giraffe 1.9 hr

The current world record for the longest period without sleep is 11 days, set by Randy Gardner in 1965. Four days into

the research, he began hallucinating. This was followed by a delusion where he thought he was a famous footballer.

Surprisingly, Randy was actually functioning quite well at the end of his research and he could still beat the scientist at

pinball. S o u r c e : B B C

Alzheimer's Eye Test

Count every ' F ' in the following text:

FINISHED FILES ARE THE RE

SULT OF YEARS OF SCIENTI

FIC STUDY COMBINED WITH

THE EXPERIENCE OF YEARS...

How many Fs you count?

.

E - M A G

17 There has only been 193,000 metric tonnes of gold discovered to date.

There are 6 Fs -- no joke. READ IT AGAIN! Really, go back and Try to find the 6 F's before.

The reasoning behind is that our brain cannot process 'OF'. Incredible or what? Go back and look again!! Anyone who counts all 6 'F's' on the first go is a genius

Submitted by: Saad Ahmed

IInntteerr SSeerrvvii cceess SSeelleeccttiioonn BBooaarrdd Written by : Abdul Salam

ISSB is a selection board of the Pakistan Armed Forces. All the selection of officers of armed forces is held under this board.

ISSB acts as nursery for the Armed Forces of Pakistan. Its Mission is to select potential officers for the defense forces of

Pakistan who have the requisite mental, moral, social and dynamic qualities to make successful leaders during peace and

war. The above mission sets a very sacred and tough challenge for the organization which can only be met with true

dedication, selfless devotion and unflinching resolve to set and meet the standards. Inter Services Selection Board follows a

set of time tested protocols to analyze and predict human.

In order to get commission in forces candidates have to be “RECOMMENDED “by the board. Candidates have to pass the

initial exam and later on medical exam at the selection centres of army, navy and air force. The candidates fulfilling the initial

requirements are then called by the board.

Candidates have to stay for 4 days at ISSB for many different tests. The selection technique followed by the ISSB is three

dimensional. All candidates appearing before the ISSB are to take three

different types of tests, i.e., psych tests, GTO tests and Interview. The

Psychologist Officers, Group Testing Officers and the Deputy Presidents, who

are specialists in their respective fields, administer these tests.

Testing Programme

1st Day

Opening Address by a Deputy President Intelligence Tests Announcement of screening out result

Remaining Psychological Tests

2nd Day

Briefing

Indoor Tasks

Group Discussion

Group Planning

Outdoor Tasks

Progressive Group Task (PGT)

Half Group Task (HGT)

Candidates at Conference day

Candidates during test

E - M A G

18 The longest recorded duration of a total solar eclipse was 7.5 minutes.

3rd Day

Individual Obstacles

Command Task

Final Group Task (FGT)

Interviews

4th Day

Conferences

Preparation of all the results

Dispersal of candidates

After taking so many different tests, all the respective officers that are observing the candidates held conference where they

discuss the suitability of the candidates for the RECOMMENDATION to the respective headquarters. After the recommendation candidates are called for final medical tests and then clearing the test will result in the joining letter to the Pakistan Military Academy, Air force Academy Risaalpur, & Pakistan Naval Academy.

DDeeffeennddeerrss ooff PPaakkiissttaann –– OOuurr PPrriiddee

E - M A G

19 Travelling by air is the safest means of transportation.

UUrrbbaann ttoo UUrrbbaann

Written by: Sami Haroon GC University, Lahore

I'm standing in the scorching heat in a sweat soaked shirt and dress pent. I look at my watch 12:30 pm. I'm waiting for the

local bus to reach a debating camp at Government College University Lahore. Let me enlighten about the fact that I used to

reach the University by its own transport, until a strange rule was imposed on us that would not allow us to gossip with even

the boys. That was when my association with the University transport ended. 'Long Live Local Busses!' wa s my slogan. I was

so wrong.

Here it comes, the 40 brutally carved at the head of the bus. I stick out a hand to remain it to stop, but the speed which it

approaches me scares me into pulling my hand back. Suddenly, it comes to a screeching halt, which al most leaves me deaf.

"Wapda Town, Lari Adda!!" the conductor shouts repeatedly and as I stick one foot into the bus, a man sitting by the

window spits paan on my new shoe and shows me a weird expression that I interpret as an apologetic smile. The bus pulls

away and I yank my spoiled shoe inside to save my leg from the passing traffic.

It's a fish market inside. My dad says, 'Son, one has to strive a lot to make his place in society'. I must be making my father so

proud because I really have to strive to find a little space for myself inside the moving fish market.

Here I am, standing, holding onto the rusting, breaking, railing separating the males from the females, both feet stuck under

the railing to hold on. I sigh deeply. The passengers will make a Maulvi proud. They are standing in a great show of

brotherhood, shoulder glued to each other.

I glance at the passengers and notice that they are giving weird looks to my dressing. I study my clothes. I don't see anything

wrong with them. May be they were not expecting a man with suit, who looks like he accidentally fell into a tub of starch

before joining the mobile fish market.

By now, I'm dying to sit. The man sitting by my side stands up and I breathe a deep sigh of relief. I'm just about to sit, when

I'm rudely pushed from the opposite side and a man jumps over several heads to land into the seat. He looks happy like he's

just dethroned Mushraf or something. It's happened so quickly, I'm wondering if maybe we finally have something with

which light travels, he is not unkind, he offers me to sit in his lap, but I just smile stiffly and turn away.

The bus stops at an unknown stop. This is nothing extraordinary. Everyday there is a new stop. A strange creature boards the

bus. It has long hairs, a long beard, dirty white shalwar kameez. The shalwar hangs about 5 inches above his ankles.

The creature is still. Suddenly it wipes its face on its chaadar and shouts, 'Attention respected passengers! Respected

passengers, I am here to tell you that there is only one God, Allah. We worship only one God and Prophet Muhammad

(S.A.W) is Allah's last Prophet. I am here to tell you . . . ` the shouting match reaches half time. It takes something out of its

bag and the shouting match resumes. 'This is a needle! I am here to tell you that this is a special needle and I guarantee that

if you buy even one of the these special needles, you will get very close to God. Right now, it is selling for 10 rupees in the

market. I am here to tell you that it is only for 5 rupees in my hand. Buy them and get close to God.

E - M A G

20

How much we understand the sign boards?

.

I smile myself. What nonsense! Who would buy it? I get my answer instantly because suddenly the fish market turns violent

as waves of men shove their 10 rupees notes forward to buy a one-way needle to God.

A man standing by my side shivers. I turn to him and he looks horrified as though I have slapped him. Then he reaches into

the pocket of his kameez and while he keeps staring at me, pulls out what I was think is going to be a gun to shoot me with.

But it's a mobile. 'My mobile is vibrating.' I don't know why he is telling me this. 'I bought this from Shah Almi for 2,325

rupees only and you know, it has a camera too. Isn't great? 2,325 only!! I nod in reply and then he asks which mobile I have,

but suddenly the conductor yells 'Katcheery!!' and I push my way to the door, swimming along with the tide.

The mobile body of flesh, sweat and dirt spits me out much like the paan I started my journey with and as I regain my

balance, I check to make sure all parts of my body have landed with me.

I reached my destination at last. But before going to the debating camp, I went to the transport office for my new bus card.

E - M A G

21 The stapler was invented in Spring Valley, Minnesota.

Photograph by: Moonis Ahmed, UET, Lahore

MMyy CCoommppuutteerr By: Burmah M. Teague

My computer has a language

That is foreign to me

It speaks of RAM and Gigabytes

And what could ROM be!

I don't understand the Windows

My computer says are there

Nor the Gem Clip at the side of my page

With eyes that blink and stare!

I don't understand the cures

That maintenance wizards do

It's called defragmenter, scan disk,

And virus cleaning too!

Yet, computer and I work hand and eye

With a mouse to translate

The tasks that I want it to do

While it points out my mistakes!

E - M A G

22 A cesium atom in an atomic clock that beats over nine billion times a second.

Su b m i t t ed b y : D i l a wer H u s s a in

TTwwiinnkk llee TTwwiinnkk llee

E - M A G

23 Hydrogen is the most common atom in the universe.

Twinkle, twinkle, little star,

How I wonder what you are!

Up above the world so high,

Like a diamond in the sky!

Following stanzas are also part of this rhyme but

only few of us might ever read these stanzas

When the blazing sun is gone,

When he nothing shines upon,

Then you show your little light,

Twinkle, twinkle, all the night.

Then the traveller in the dark,

Thanks you for your tiny spark,

He could not see which way to go,

If you did not twinkle so

In the dark blue sky you keep,

And often through my curtains peep,

For you never shut your eye,

Till the sun is in the sky

As your bright and tiny spark,

Lights the traveller in the dark,—

Though I know not what you are,

Twinkle, twinkle, little star

Do you know?

The poets of this poem were two sisters Ann Taylor (1782-1866) and Jane Taylor (1783-1824). This poem was

first published in 1806. It is often sung to the tune of the French melody "Ah! vous dirai-je, Maman" which was

published in 1761.

SSmmiillee PPlleeaassee

E - M A G

24 One tree can filter up to sixty pounds of pollutants from the air each year.

Never put off the

work until tomorrow

- what you can put

off today!

E - M A G

25 The first domain name ever registered was Symbolics.com on March 15, 1985.

A person turned on the computer without a

keyboard plugged in.

When she turns on the computer, the computer

finds out that there is no keyboard attached

and it gives a "Keyboard Error" message.

She then asks "Why did it give me a keyboard

error?

There isn't even a keyboard attached?

I was thinking of

becoming a doctor.

I have the

handwriting for it.

A modern artist is one who

throws paint on canvas,

wipes it off with a cloth

and sells the cloth.

TTeesstt YYoouurrsseellff!! Submitted by: Mobeen Afzal

Continue the following sequence in a logical way:

M T W T _ _ _

Correct this formula with a single stroke:

5 + 5 + 5 = 550

Please write anything here:

___________________________________

Draw a rectangle with 3 lines:

E - M A G

26 The USSR launched the world's first artificial satellite, Sputnik 1, in 1957.

Note: Answers will be published in next edition.

Submit your answers at editor.emag@gmail.com before April 25, 2009

Your name would be published in next edition of E-MAG if you submit correct answers

This test has been taken from a test paper of A Level.

Solutions of

Logical Puzzles By: Saad Ahmed

If it were two hours later, it would be half as long until midnight as it would be if it

were an hour later. What time is it now?

9 p.m.

One brick is one kilogram and half a brick heavy. How heavy is one brick?

There is an easy equation which can help: 1 brick = 1 kg + 1/2 brick And so 1 brick is 2 kg heavy.

A table tennis ball fell into a tight deep pipe. The pipe was only a bit wider then the ball, so you cannot use your hand. How would you take it out, with no damage?

All you have to do is pour some water into the pipe so that the ball swims up on the surface.

A man lives on the tenth floor of a building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator - or if it was raining that day - he goes back to his floor directly. Otherwise, he goes to the seventh floor and walks up three flights of stairs to his apartment. Can you explain why it is so? (This is probably

the best known and most celebrated of all lateral thinking puzzles. It is a true classic. Although there are many

possible solutions which fit the initial conditions, only the canonical answer is truly satisfying.)

The man is a midget. He can't reach the upper elevator buttons, but he can ask people to push them for him.

How can you throw a ball as hard as you can and have it come back to you, even if

it doesn't hit anything, there is nothing attached to it, and no one else catches or

throws it?

Throw the ball straight up in the air.

E - M A G

27 The width of a tornado can range from less than ten yards to more than a mile

Sudoku is a number placement puzzle. The objective is to place digits in 9 x 9

grid such that digits from 1 to 9 occur once in each row, each column and each

3 x 3 boxes (blocks). Some numbers are already given at random places. Player

has to fill the remaining boxes according to above constrain.

Solution of last month

Correct Solution Submitted by:

Aamna Yousaf Mir - 06-poly-07 - UET, Lahore

Muhammad Rizwan Asghar - BCSS02A023 - PUCIT

SSUUDDOOKKUU

8

7 3

4 5

2 1

4

3 6

8 5

9 5

2

3 6

1 8

4 9

7

8 3 4 7 6 5 1 2 9 1 7 5 8 2 9 3 4 6

6 9 2 1 4 3 7 8 5 4 6 8 3 9 7 5 1 2

7 2 3 5 1 6 8 9 4 5 1 9 2 8 4 6 3 7

3 4 6 9 5 1 2 7 8

2 5 1 4 7 8 9 6 3 9 8 7 6 3 2 4 5 1

E - M A G

28 The only commercial aircraft that is able to break the sound barrier is the Concorde

Note: Solution of above Sudoku will be published in next edition.

Submit your answers at editor.emag@gmail.com before April 25, 2009

Your name would be published in next edition of E-MAG if you submit correct answers

PPrrooggrraammmmiinngg CChhaalllleennggeess By: Mian Zeshan Farooqi

1. Simply add a single character in the following co de such that it prints Long Live

Pakistan o nly one time. Yo u’re not al lowed to modify or remove any character.

2. Write a progr am which takes two positive integers from user and displ ay the

greater o ne . You’re not allo wed to use < or > operator in your co de.

3. Write a progr am which dis plays 0 i f the given integer is even and 1 if odd.

You’re not allowed to use any arithmetic operator . By: Dil awer Hussai n

4. I was said to write a progr am which prints 786 on scr een. By mistake I added &

operator in co ut statement. Now as a penalty I ’m not allo wed to remove or

modify anything from my co de. I’m said to fix this mistake by adding one more

character in the fo llowing code . Which char acter sho uld I add to print 786 o n

screen?

E - M A G

29 Every day, the Hubble telescope transmits enough data to fit 10,000 standard computer disks.

#include <iostream.h> void main () {

for ( int i = 0; i < 10; i++ ) cout<<”Long Live Pakistan”;

}

D iff ic ul ty : 1

#include <iostream.h> void main () {

int var = 786; cout<<&var;

}

Note: Answers will be published in next edition.

Submit your answers at editor.emag@gmail.com before April 25, 2009

Your name would be published in next edition of E-MAG if you submit correct answers

SSoolluuttiioonnss ooff PPrrooggrraammmmiinngg CChhaalllleennggeess

((11sstt eeddiitt iioonn))

Change the following code to print ASCII of ‘A’. You’re allowed to add/remove or edit

maximum five characters in the following code.

Change the following code to print ‘I Love Pakistan’ ten times. You’re allowed to add/remove

or edit maximum one character in the following code.

E - M A G

30 The Great Comet of 1843 had a tail that was over 300 kilometres long.

#include <iostream.h> void main () {

int ch = ‘A’;

cout<<ch; }

#include <iostream.h> void main () {

char ch = ‘A’;

cout<<(int)ch; }

Correct Solutions Submitted By:

Ali Younas – BSEF07A010 – PUCIT Samia Amjad – BITF08M036 – PUCIT

Muhammad Rizwan Asghar – BCSS02A023 – PUCIT Muhammad Ammar Aslam – BSEF07A037 – PUCIT

#include <iostream.h> void main () { int n=-10; for(int i=n; i<0; i++) cout<<”I Love Pakistan”; }

#include <iostream.h> void main () { int n=10; for(int i=-n; i<0; i++) cout<<”I Love Pakistan”; }

Note: If you want to discuss these problems then you can contact me at zeshan.farooqi@yahoo.com

Correct Solutions Submitted By:

Ali Younas – BSEF07A010 – PUCIT Muhammad Ammar Aslam – BSEF07A037 – PUCIT

D iff ic ul ty : 1

Table 2.1

sizeof() function takes one parameter i.e. data type or variable and returns its size in number of bytes. For example if you execute the following

code on BC++ then it will display 2 which means int takes 2 bytes under environment of Borland C++

void main () {

cout<<sizeof(int);

}

Learning C++

By: Mian Zeshan Farooqi

In the previous episode, we learnt some basic concepts of C++. We learnt to include header files, displaying something on scr een,

clrscr() and getch() functions, stream insertion operator <<, use of endl and a escape sequence ‘\n’. In C++ \ is known as escape

character. Some character is when combined with this \ then it is (as a whole) known as escape sequence. We use escape sequences in

strings for output. When compiler encounters an escape sequence, it doesn’t print that, instead it performs some specifi c task. Some

commonly used escape sequences are given in Table 2.1 with their corresponding functionality. I would advice you to use these escape

sequences in your programs to beautify their outputs.

Now let’s move towards the input operations and memory concepts. Input means to take the response from user (via keyboard, mouse,

etc) or from some file or other source. Before going into

details, let us take an example from our daily life.

Consider that you want to drink juice of oranges today.

You have oranges and a juicer machine with you, is it

enough? Think upon it! Would you put the oranges in

juicer machine, extract the juice and put your mouth in

front of machine to drink the juice? Obviously as a

civilized person you would not do like that. You would

take some glass and extract the juice in it and then drink

that juice. So being more generalize we can say that you

would take some container and pour the juice into it.

Now this container might be a class or a bottle or

anything else. It means that we always need a container to keep something. Same like that in C++ we need some container to store the

data for our program. Now what could be that container? Should I take some glass or a bottle like above example to store the data for

my program? Obviously not! We can’t use same thing for different situations. Here I would need some free memory location to store my

data. We can find free memory locations in main memory (i.e. RAM) or hard disk or any other storage device. As you know that

Operating System loads every program in main memory, so it allows us to store our data temporarily in main memory during the

execution of our program.

What we do is that we occupy some memory locations temporarily in main memory and name those locations. These named memory

locations are known as identifiers. We also define attributes of identifiers e.g. which type of data it can store, life time, etc. Occupying

space and assigning it some name is known as declaration of identifier. While assigning it some initial value is known as its initialization.

An identifier whose value can never be changed (after initialization at the time of declaration) is known as a constant identifier or simply

as a constant. Those identifiers whose value can be changed any time during

execution of program are known as variable identifier or simply as a variable. Have a

look at the following code:

1. void main () 2. { 3. int a; 4. const int b = 123; 5. a = 10; 6. }

Escape sequence

Name Description

\n New Line Moves the cursor to the start of next l ine.

\t Tab Moves the cursor one tab ahead .

\r Carriage Return Moves the cursor to the beginning of current line.

\a Alert Produces a beep from PC Speaker.

\b Backspace Moves the cursor one character reverse.

\\ Backslash Prints a backslash.

\' Single Quote Prints a single quote.

\" Double Quote Prints a double quote.

E - M A G

31 The United States has paved enough roads to circle the Earth over 150 times.

Episode # 2

A constant identifier can never contain

a garbage value because we’re bound

to initialize it at the time of declaration.

A valid C++ identifier name starts with

an alphabet or underscore and

preceding characters can be letters,

digits or underscore. You can not use

a keyword as an identifier name.

Valid names Invalid name

abc 123 var1 1var temp_1 temp 1 _sum sum!

A modifier is a keyword which is used to

modify the default meaning or use of a

basic data type. A modifier is always

placed before the data type in declaration.

In line 3 we’ve declared a variable identifier of name a. The first word of line 3 int is telling the compiler that which type of data a can

store. It is known as data type of an identifier. There are some basic data types in C++

which are known as built-in data types. These are int, char, float, double, void. int stores

an integer value like 123, char stores a single character like ‘A’ and float contains a decimal

value like 123.456. At this level you can consider double as an enhanced form of float. void

is usually used only as a return type of function because it holds nothing. There’re some other built-in data types like wchar_t but we’ve

no need to focus on them at this level.

Size and range of these data types varies from machine to machine. You can use sizeof() function to determine the size of a data

type. In this case data type of a is int that is indicating that a can store an integer value. The size of a in memory is automatically

determined by the compiler. Initially a contains an unknown value which is known as garbage value.

In line 4 we’ve declared a constant identifier of integer type named as b. Here const is an

access modifier of identifier b which means that value of b can never be changed. It

means we must assign some initial value at the time of declaration of a constant

identifier. While you can initialize any non-constant identifier (variable) at any time

during the execution of program, as we’ve declared a at line 3 and initialized it at line 5.

Note that we’ve to specify the data type of an identifier only at the time of its declaration, after that we can access the occupied

memory location simply with the name of its identifier. So line 5 will place 10 at the memory location whose name is a.

You can’t declare multiple identifiers of same name in same block. For example consider the following code

1. void main()

2. {

3. int var2;

4. int var2 = 10; //error – var2 is already declared

5. }

You can create multiple variables of same data type with comma separated list or in separate lines. Its totally upto you either you initialize all of them ,few of them or none of them at the time of declaration. See the following code:

1. void main()

2. {

3. int num1, num2 = 5, num3 = 0, num4, num5, num6;

4. char name1 = ‘A’, name2, name3, name4, name5 = ‘F’;

5. float alpha = 2.2, beta = 3.243, gamma = 9.999;

6. int var = -10;

7. } You’ve created total 7 int type variables out of which 3 are initialized. 5 char type variables out of which 2 are initialized and 3 float type variables and all of them are initialized at the time of declaration.

E - M A G

32 The iron disulfide (Pyrite) is considered "fool's gold" because it looks very similar to gold.

A keyword is a word reserved by the

language to provide various

features. A keyword has can not be

used as an identifier. You can get the

list of C++ keywords from E-MAG

website. http://emagportal.com

Table 2.2

There are some data type modifiers named as unsigned, signed, long, short. The modifiers signed, unsigned, long, and short can be applied to integer base types. In addition, signed and unsigned can be applied to char, and long can be applied to double. All combinations and effects of using these modifiers are given in table 2.2. Now I would like to introduce two more concepts i.e. scope of an identifier and life time of an identifier. Life time of an identifier is the

duration for which it exists in the memory. Scope of an identifier is the area of your source code in which you can access that identifer.

We’ll learn both these concepts side by side. Consider that you’ve two functions in your program, one is main() and other is myfun().

A variable a is declared in main () and another variable b is declared in myfun(). Now you can’t access a in myfun() and it is also

not possible to access b in main(). Such identifiers which are accessible only in the block of code ( area between { and } ) in which they

ware declared, are known as local identifiers. While such identifiers which are accessible anywhere in the source code, are called global

identifiers. Have a look at the following source code:

1. #include <iostream.h> 2. 3. int var1 = 10; //global variable 4. void myfun()

5. {

6. int var2 = 10;

7. var1 = 123; // allowed

8. var3 = 20; // error – undefined symbol var3

9. }

10. void main ()

11. {

12. int var3 = 10;

13. var1 = 10; // allowed

14. var2 = 20; // error – undefined symbol var2

15. }

In above example we’ve declared a global variable var1 at line 3. var1 is accessible to both main() and myfun(). var2 is

declared in myfun() and var3 is declared in main(). You can see that we’re unable to access var2 in main() and var3 in

myfun(). This is because var2 is declared in block of myfun() so it is accessible only in that block and same is the case of var3.

Now let’s have another example to better understand the scope of a variable. Consider the

following code:

1. void main () 2. { 3. //create a logical block of statements

4. { 5. int a = 2; 6. } 7. cout<<a; //error – undefined symbol a 8. }

Type Size

(bits) Range

char 8 –12 8 to 1 27

unsigned char 8 0 to 25 5

signed char 8 –12 8 to 1 27

int 16 –32, 76 8 to 3 27 67

unsigned int 16 0 to 65 53 5

signed int 16 –32, 76 8 to 3 27 67

short int 16 sa me a s in t

unsigned short int 16 sa me a s u ns i gne d in t

signed short int 16 sa me a s sh o rt i n t

long int 32 –2,1 47 ,48 3, 648 to 21 47 48 364 7

unsigned long int 32 0 to 42 94 967 29 5

signed long int 32 –2,1 47 ,48 3, 648 to 21 47 48 364 7

float 32 3.4E –3 8 to 3. 4E+ 38

double 64 1.7E –3 08 to 1.7E +3 08

long double 80 3.4E –4 932 to 1. 1E+ 493 2

E - M A G

33 The first subway system in America was built in Boston, Massachusetts in 1897

There’re two terms, declaration and

definition. Declaration of an identifier

assigns some name to that identifier

while definition allocated it some

memory. As declaration and definition

are usually done at a same time in C++

so we use a single term.

First of all keep this thing in mind that usually we do not create such blocks as I’ve created in above example (line-4 to line-6). Such

blocks are usually created for loops and if-else conditions but as we’ve not yet learnt about any of these concepts so I’ve simply created

this dummy code, but doing this is not an error. Now coming back to our original discussion, can you guess why compiler will show an

error at line 7? Let’s see why. We created a block at line-4 and declared a variable a in that block. Now a is in memory. But when we

came at line 6, our block is finished here. So everything inside this block is also finished. Now a is no more accessible. It means that life

time of a from line 4 to line 6.

Let’s move towards a more interesting case. As you’ve seen that you can not declare multiple variables or constants with same name.

But have a look at the following code:

1. void main () 2. { 3. int a = 20; 4. { 5. int a = 2; 6. cout<<a; 7. } 8. cout<<a; 9. }

You can see that we’ve declared a twice in main() but still there’s no error. What’s the reason? The reason is the scope of variable a.

Variable a declared at line 3 is accessible anywhere in main() but the other variable a which is declared at line 5 is only accessible in its

own block. It will destroy at line 7 because its life time was from line 4 to line 7. While the life time of first one a is the whole

main().So run and check the output of this program.

Now I’m going to cover the last topic of this episode i.e. storage class specifiers. Storage class specifiers are also keywords which

determine that how a variable will be stored. There’re five storage class specifiers in C++ i.e. auto, extern, register, static and mutable.

auto is a storage class specifier which declares a local variable. By default a variable is declared locally i.e. auto int var; and int

var; are equivalent statements. So usually we do not use auto in our code.

Variables declared with static specifier remains in the memory throughout the execution of program. A variable is usually being

destroyed when it becomes out of scope. But variable declared with static storage class specifiers remains in the memory throughout

the program execution. register specifiers requests the compiler to store the variable at such location from which it can be accessed

with a fast speed. extern specifier only declares a variable, it doesn’t defines variables. mutable is applied only to class object. We’ll

discuss both extern and mutable later because we’ve no need to understand them at this level.

E - M A G

34 Cubic Zirconia is 55% heavier than real diamonds

Author’s notes: I received some emails that the speed of this article is very slow and it will not cover all concepts in one semester.

Yes it is true. But let me make this thing clear that programming concepts are not only for one or two semesters. As a programmer

you’ll need these concepts throughout your life. Therefore it is necessary to make a strong foundation. Many students need to re-

study the fundamental concepts of programming after reaching at an advance level. This is only because they don’t have strong basic

concepts. So do less but do well and remember that slow and steady always wins the race.

If you need any kind of help regarding C++ then feel free to contact me at zeshan.farooqi@yahoo.com

EExxpplloorree WWiitthh MMee By: Mian Zeshan Farooqi

How to get and set date in C/C++?

There’s a date structures and two functions getdate() and setdate() defined in dos.h.

(You can consider structure as a group of variables). This structure allows you to get and set

the current system date:

struct date{

int da_year; /* current year */

char da_day; /* day of the month */

char da_mon; /* month (1 = Jan) */

};

How to use get or set the date?

#include <iostream.h>

#include <dos.h>

void main ()

{

struct date d;

getdate(&d);

cout<<”Date:\t”<<da_day;

cout<<”Month:\t”<<da_mon;

cout<<”Year:\t”<<da_year;

}

#include <iostream.h>

#include <dos.h>

void main ()

{

struct date d;

d.da_day = 14;

d.da_mon = 8;

d.da_year = 1995;

setdate(&d);

}

E - M A G

35 A cubic yard of air weighs about 2 pounds at sea level.

This monthly segment describes

different functions of C/C++

Get Date Set Date

TTiippss aanndd TTrriicckkss

CChhaannggee DDrriivvee LLeetttteerrss::

Go to Start > Control Panel > Administrative Tools > Computer Management, Disk

Management, then right-click the partition whose name you want to change (click in the

white area just below the word "Volume") and select "change drive letter and paths."

From here you can add, remove or change drive letters and paths to the partition.

RReemmoovviinngg MMuullttiippllee BBoooott SSccrreeeennss::

If you are getting unwanted multiple boot screen, Then Follow these Steps.

1. Right Click on My Computer

2. Select Properties

3. Select Advanced Tab

4. Select Settings In the Start-up & Recovery Section(3rd group)

5. Select the operating system which u want, click OK.

6. Further again press the setting and click on Edit. It will open boot.ini File.

7. Now u can delete those o/s which you don't want to be displayed.

Note: For deleting operating systems from boot.ini file, keep it mind that you can't

delete that o/s which is selected by default there. Before

making any changes make a copy of boot.ini file.

E - M A G

36 The first spacecraft to visit the planet Venus was Mariner 2 in 1962.

SSooffttwwaarree ooff tthhee MMoonntthh

Autodesk® Maya® Complete

Autodesk® Maya® Complete software is a comprehensive suite of 3D tools for

modeling, animation, and rendering within a single, production-proven workflow.

Maya Complete—the choice of award-winning digital artists and animators—has an

intuitive design that makes it a favorite among digital content creation artists and

enthusiasts of all experience levels who develop artwork for film, broadcast, game

development, multimedia (print and web) or design visualization.

Maya Complete 2008 includes toolsets for:

Modeling

Animation

Visual Effects

Rendering

Paint Tools

Toon Shading

PLUS:

Maya API/SDK, Python® and MEL Scripting

Tutorials and Documentation

Just for information: Maya was originally released for the IRIX operating system, and

subsequently ported to the Microsoft Windows, Linux, and Mac OS X operating systems. IRIX

support was discontinued after the release of version 6.5. When Autodesk acquired Alias in

October 2005, they continued Maya development. The latest version, 2009 (10.0), was

released in October 2008.

Download Link: http://www.autodesk.com

E - M A G

37 The word "laser" stands for "Light Amplification by Stimulated Emission by radiation."

Overview by:

Dilawer Hussain

UUsseeffuullll LLiinnkkss

SpeedTest.net

Test the speed of your internet connections from different servers all around

the world. This site recommends you a server to test your connections from but

also allows you to test from any other server around the globe. You can also

compare your results with other people who’re using the same ISP in your

region or with those who tested their connection from this site.

TvChannelsFree.com

This site allows you to different Tv channels online. It has links to more than

4000 tv channels around the world including, news channels, video channels,

entertainment channels, etc. This huge collection is now available to you for

free of cost. Another interesting thing, it allows you to stream same channel

from different servers.

Maps.Google.com

You can find the map of whole world here. Zoom-in and zoom-out the locations.

Explore every city of your country. This service of Google is also free of cost. As

Google earth provides you an enhanced view of the earth. But if you’re at a

place where you don’t have enough time to download and install the Google

earth, then just open this website and do your work.

E - M A G

38 Every second, 630 steel cans are recycled.

TThhee CCoonnssttiittuuttiioonn ooff TThhee IIssllaammiicc RReeppuubblliicc ooff PPaakkiissttaann,, 11997733

PPaarrtt –– II

Article: 1 The Republic and its territories

1. The Republic and its territories. -- (1) Pakistan shall be a Federal Republic to be known as the Islamic Republic of Pakistan,

hereinafter referred to as Pakistan.

1 [(2) The territories of Pakistan shall comprise-]

(a) The Provinces of Baluchistan, the North-West Frontier, the Punjab and Sindh;

(b) The Islamabad Capital Territory, hereinafter referred to as the Federal Capital;

(c) The Federally Administered Tribal Areas; and

(d) Such States and territories as are or may be included in Pakistan, whether by accession or otherwise.

1 [(3****)] deleted.

1 [(3) 2[Majlis-e-Shoora (Parliament)] may by law admit into the Federation new States or areas on such terms and

conditions as it thinks fit.]

Article: 2 Islam to be State religion

2. Islam to be State religion.-Islam shall be the State religion of Pakistan.

Article: 2A The Objectives Resolution to form part of substantive provisions

1[2A. The objectives Resolution to form part of substantive provisions.-The principles and provisions set out in the Objectives

Resolution reproduced in the Annex are hereby made substantive part of the Constitution and shall have effect accordingly.]

1. Item 2 of the Schedule to P.O. No. 14 of 1985 inserted Art. 2A. (w.e.f. March 2, 1985).

E - M A G

39 Bamboo plants can grow up to 36 inches in a day.

Episode # 1

MMAAGG NNEEWWSS

March 26, 2009 – A National Seminar on “Arabic Language in Pakistan, Its Past,

Present and Future” was conducted by Department of Arabic, University of the

Punjab. The seminar was conducted in senate hall. Chief guest was Sahabzada

Noor-ul-Haq Qadri, Federal Minister of Zakat and Usar, Govt. of Pakistan. Profes sor

Dr Mujhahid Kamran, Vice Chancellor, University of the Punjab, Presided the

seminar. There were a huge number of faculty members and students from

different universities of Pakistan, who attended the seminar.

March 29, 2009 – First tape ball tournament started at PUCIT. There’re total 16

teams. Tournament would be go on knock-out basis. The event is organized by Mr

Fareed-ul-Hassan Baig, Faculty member of PUCIT. Matches are being played at

ground of Khalid-bin-Waleed Hostel. Final match would be played on Monday, April

6, 2009.

March 30, 2009 – An Islamic Quiz and speech competition was arranged by E vent

Management Society, PUCIT. For quiz competion there were 9 teams. Each team

consist of 3 members. Topics were Seerat-e-Tayyaba, Sahaba and Ghazwat. All

matches were played on knock out bases. Quiz competition starts at 11:00 am. Mr

Aasim Rasul and Ms Qudsia Hamid were judges.

E - M A G E - M A G

40 In 1903 Mary Anderson invented the windshield wipers

Honourable guests during seminar

Teams during competition

Players during match

PPiiccttuurreess ooff PPaakkiissttaann

E - M A G

41 At lift off, US space shuttles weight about 4.5 million pounds.

Source: Geo Tv, BBC, CNN, Yahoo News, Reuters, AP

A new monthly segment under MAG NEWS

Before and After Long March

E - M A G

42 The first jet engine was invented by Frank Whittleof of England in 1930

Source: Geo Tv, BBC, CNN, Yahoo News, Reuters, AP

Attack on Police Academy Manawan, Lahore

NNOOTTIICCEESS

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E - M A G

Copper is the second most used metal in the world

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