unsend a sent email from gmail account

Oops sent a wrong email from your gmail account.It happens often that you accidentally sent an uncomplete email or an email to wrong reciepent, the only thing you can do is regret.But dont worry now the latest added feature in gmail "undo send"will let you do the trick.

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NOw you can easily unsend a sent email from your gmail account by following the simple steps given below :

1. first of all open your gmail account
2. Now go to the settings at right top corner of the screen
3. under the setting option again click to the setting option

4. now the setting window will appear ,under this enable the undo send option
5. The best part is that you can also set the time limit to unsend an email,but the maximum time limit is 30 secind if you choose undo option within that time frame then you email could get unsent but if you tried to undo send it after that time limit than you will encounter failure

6. To understand it fully let us perform it practically
7. compose an email to any additional email account if you have,otherwise you can also try it to you r friend or family member whom you can easily access
8. send the mail
9. after sending your mail a message will appear like this on your gmail window displaying the undo,view and message option in a yellow bar

10. now click the undo option
11. ta da you have just unsend a sent email
12. You can check by logging in the account to which you have sent a mail that whether your mail was recieved or not

why is lolipop better than kitkat??

We all know lolipop is latest version 5.0 and 5.1,some devices with kitkat are recieving updates for lolipop,but is it worth getting lolipop update,if yes then why ??

the features in lolipop which make it way more better than kitkat are listed below

1. Inbuilt Flashlight
It would always be puzzling as to why Google did not pin a flashlight  in our notifications panel just like iOS has in its control center.  Lollipop brings out that change. Without installing any third-party  apps, users can simply use the flashlight by pulling down the  notification panel. Make sure your smartphone has an LED flash.

2. Battery changes
Battery seems to be given priority in Android Lollipop. No longer do  users have to lay bets on how long their battery would last for. The new  OS has two new and much needed features which were not available on  KitKat. It shows you how long it would take to charge your phone and a  small graph showcasing how much time is left before the battery runs  out. After you have plugged in your phone for charge, your home screen  will show you the time until full charge.

3. Guest user
We all have people around us who lay their hands on our phones.  Thankfully, Android Lollipop helps us with this issue. Just like  different Users in Windows, Lollipop gives you the liberty to add guest  users or even create a profile for a friend/relative. This way, you can  limit the amount of information that others can view. You can add a  guest by simply going to Settings – Users – Add Guest.

4. Flappy Bird easter egg
If Flappy Bird wasn’t frustrating, Lollipop offers you a modified  version of the game. Instead, here you have an Easter egg to unlock.  Users can go to Settings – About phone and click several times and you  will get the android robot in place of the bird.

5. Notification panel
Needless to say, the notification panel has been made too simple for  the user. It’s simplicity in design is the plus point. Unlike KitKat,  the most useful feature added here is the ability to view your detailed  notifications on your lock screen. Though this might be a problem around  work spaces if you leave your phone unattended, anyone can have a look  at your notifications even though your phone is locked. It can be  disabled by going to Settings – Sound and Notification – When device is  Locked – Don’t show notifications at all.

6. Trusted Places
Trusted Places is a smart feature which has been added in to  Lollipop. Though most of our phones have passwords, it would be a task  to disable it when we enter familiar premises such as our car or home.  Trusted Places is a feature where a user can declare certain locations  as safe and they wouldn’t need to unlock their phones once they enter  those spaces. You can set the location by heading to Settings – Security  – Smart Lock.

7. Soft key redesign
Soft key buttons receive a change in this update and it is a rather, a  surprising change. The icons are smaller and look compact. A very  simple yet pleasant design.

8. Multitasking 
Multitasking has completely changed in Android Lollipop. The feature  allows you to scroll through your notifications in a simpler manner. It  is easier and allows you to see more details even before you enter the  app.

9. Prioritize apps
It can be super annoying if your phone is filled with umpteen apps  and throughout the day, you are bombarded with notifications. Lollipop  gives you the liberty to prioritize your apps so that you can receive  notifications from the ones you want. It works out perfectly during  sleep hours as you can only receive notifications from important apps  and not games or check-in notifications.

10. Quick access to Chromecast   
No need to install any third-party apps once you have the updated  your phone to Lollipop. There is an official app now from Google to  solve our problems. For the people who love to stream media from  dongles, it is as simple as going to the notification panel and taping  on Cast Screen.

THE FOLLOWING BLOG DISCUSSES ONE OF THE MOST CONFUSING TOPIC OF JAVA ... i.e. 
                 JAVA SHADOWING
I'M SURE THIS POST WILL BE A BOON FOR JAVA PROGRAMMERS ........ 


Hiding a variable is  called shadowing. A variable can be shadowed if another variable  exists in its scope. So what is a scope?

Scope =>

Scope is a region of program within which a variable can be accessed. Each type of variable have their own scope. So if there are two variables with same name in the same scope then they will be shadowed. There are different scenarios in which variables are shadowed.

CONSIDER THE FOLLOWING EXAMPLE .....

In this example .....x = 0 is overshadowed by x = 1 which is further overshadowed by x = 23.We can access them by casting instance variable to the super class variable .

             
 In the above program comment the JAVA lines 8 & 9 and this will help you to access the variable of the class ShadowTest also .

I HOPE THIS POST WILL  HELP THE CODERS TO UNDERSTAND THE SIMPLE CONCEPT OF JAVA SHADOWING ....

How To Check if Your PC is Windows 10 Compatible

With Windows 10 coming on July 29, you'll want to make sure your PC, applications and various devices will all play nice before you reserve and upgrade. Fortunately, Microsoft has made it easy to do within the Get Windows 10 tool that appears on all copies of Windows 7 and 8.

Upgrading your copy of Windows to 10 should be seamless, but you want to make sure set up is actually ready beforehand. That new Windows icon down in your system tray will let you do more than reserve your copy of Windows 10 for free. It can also check your whole system to make sure everything is all set for the upgrade. It's pretty simple to do:

* Click the Get Windows 10 icon in your system tray in the lower-right section of your desktop.
* Click the hamburger menu in the upper-left corner.
* Under "Getting the upgrade," select Check your PC.

If you're all set and ready for the upgrade when it comes, you'll be given a good to go message. Otherwise, you'll see a list of devices and apps that aren't supported.

Device issues could mean a monitor won't display properly at the highest resolution, or some speakers won't be able to play audio with the upgrade. Apps that are listed as unsupported will need to be uninstalled before you start the upgrade process. Of course, a driver update or patch install may fix those issues as well, so check again if you can find updates.

Welcome To The Future

Its the sad but consistent rule of technology that all cool future inventions must be given really terrible,confusing and complex names.The first time electronic products like washing machines and dish washers got their own brains and were able to figure things out for themselves,the name given to that technology was "Fuzzy Logic".The first time computing and storage power was taken offsite and made available from a remote location,the simple name it was given was cloud computing.And now the latest buzz is that soon each and every device,machine and sensor in the world will talk to each other and take smart decisions with zero intervention from you.The awesomely name for this  future technology? The Internet of Things(IoT). The prediction is that,in a few years from now,more than 100 billion devices will talk to each other,analyse,take decisions,change things and perfect our lives without us getting involved.

• NETGEAR's ARLO:   
  

Think about every nightmare associated with setting up an internet-accessible security camera system:wires all over,complex set up and almost impossible task of installing outdoor cameras.
Netgear's arlo is completely wireless,runs for about six month on batteries and can be set up literally by anyone in five minutes.The cameras are weather proof and can be set up outdoors or indoors.It also provides actual hd picture,great wireless range of 150 feet,perfect clarity even in the dark,and finally whole system is motion-activated. you can set up the system in few minutes. You take the main hub and connect it to your home router with an ethernet wire,then press the button on the hub and on each camera one by one. The app on your phone will allow you to record only when it detected motion. Any movement and video will be sent to you with an alert.It work perfectly as a baby monitor.At any given time  you know who was at your home hen you were two continents away.The system also talk to other devices and the cameras can be used for other IoT activities.It could turn your house lights on as soon as the cameras recognise you as you enter. It could integrate with Lifx LED light bulbs and also eventually with your home's front door lock. You could turn on ac and coffee machines before you reach home or wake up.

• THE GADGETS ARE COMING:  Xiaomi has had a head start on its IoT ambitions with a slew of new launches: the Mi Smart Weigh Scale that records  BMI and other health parameters along with your weight talks to your phone and fitness band(yes,fitbit and withings have similar features  but this one talks to a whole lot device and costs $20).There is Yeelight Beside lamp,which is completely controllable via your smart phone,throws out light in 16 million colours,can be controlled by your gestures and soon recognise your prsesnce in the room and turn on.
  

This is just the start.The Internet of Things is coming at you from all directions and at the speed of light.

How to increase your Internet Connection speed via Ethernet Cable?? (Mechanical or physical Method)

For the first glance someone thinks that this method is just for Befooling the people. But its not true. Infact the connection speed almost gets "double" using this.

For this method CAT5 and CAT6 ethernet cable is advisable to use. 

So here we go .......

1. Firstly you need to buy a LAN wired cable and hold the cable in your hands firmly.

1. Now you need two "AA" batteries and an insulated tape .

You are now ready to boost up you connection. All you need to do is....

• fix the two batteries on the two ends of the wire near to the RJ plugs .
• Fix them in such a manner that both the terminals have their +ve terminal inwards.

Now You can use them with your ethernet enabled Internet connection and check the Difference Yourself....

Create a Bootable USB Drive without Using any Software

Hi friends here I am going tell you the easiest method to make a USB drive bootable. For this you need no external software. Infact you can carry it with the help of command prompt. You need to follow the steps as below ---

1. Insert your USB flash drive to your running computer. As the first step, we need to run Command Prompt as administrator. To do this, we need to find cmd by typing 'cmd' in the search box on Windows Start Menu. After search result for 'cmd' appears, right click on it and select "Run as administrator".
2. Type 'diskpart' on Command Prompt (without quotes) and hit Enter. Wait for a while until the DISKPART program run.
3. Type 'list disk' to view active disks on your computer and hit Enter. There would be seen that the active disks shown as Disk 0 for hard drive and Disk 1 for your USB flashdrive with its total capacity.
4. Type 'select disk 1' to determine that disk 1 would be processed in the next step then hit Enter.
5. Type 'clean' and hit Enter to remove all of data in the drive.
6. Type 'create partition primary' and hit Enter. Creating a primary partition and further recognized by Windows as 'partition 1'.
7. Type 'select partition 1' an hit Enter. Choosing the 'partition 1' for setting up it as an active partition.
8. Type 'active' and hit Enter. Activating current partition.
9. Type 'format fs=ntfs quick' and hit Enter. Formatting current partition as NTFS file system quickly.
10. Type 'exit' and hit Enter. Leaving DISKPART program but don't close the Command Prompt instead. We would still need it for next process.

Your device is ready to boot now...

HOW  TO  REMOVE  A VIRUS  WITHOUT  USING  ANY  ANTIVIRUS SOFTWARE ????

FOLLOW  THESE  SIMPLE  STEPS :-

1. Open the COMMAND PROMPT  ( either by CTRL+X  or type "cmd" in 

RUN dialog box)
2. Select the virus affected drive .
3. Type the following command -> type attrib -s-h *.*/s/d and press enter.
4. Type this command -> type dir 
     This command will show content of the drive .
5. Check if there is an unusual.exe file.
    If there is an autoruninf.file then rename it .
    Renaming is done like this => rename filename.extension newfilename

THESE STEPS WILL ALLOW YOU TO ACCESS THE  DRIVE WITHOUT  

AFFECTING THE VIRUS .
NOW FOLLOW THESE STEPS :-
1. Go to My Computer
2. Select the drive .
3. Delete the harmful files either directly or by typing the following 

command in Command Prompt => type delfilename 

SO AFTER THESE STEPS YOUR SYSTEM'S VIRUS IS REMOVED WITHOUT 

ANY ANTIVIRUS SOFTWARE .

Make Your PC talk

Hello friends we are always ready to help you and reveal out some special features about your pc which you do not know

Well as the name suggests this post is all about make your pc talk. There are two real time methods that can be used . One is programming based and other is simply the alternartive. All you need to do is simply copy and paste the following text in notepad.....

Dim msg, sapi

msg=InputBox("Enter your text","Talk it")

Set sapi=CreateObject("sapi.spvoice")

sapi.Speak msg

Now save this file with "Make Your pc Talk.vbs" 

This will simply create a scripted file. Type the text and click on OK button to enjoy your talking app.. 

why is %d used not %i for printing integers ??

Why format specifier for integer is %d not %i in c programming language?

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Have you ever wondered that format specifier written in c language like character type has %c ,float type has %f and string type has %s but integer type doesnt have %i instead it has its format specifier %d?
This is because integer is divided into subcategories decimal integer, binary integer,hexadecimal integer and octal integer and %d is used for decimal integer as its format specifier and the results we often want is of decimal type if we want our solution then different fomat specifier can be used to obtain the desired output

• %d - decimal integer
• %o - octal integer
• % x- hexadecimal integer

Note:there doesn't exists any format specifier for binary integer.

stay tuned to our blog for keep getting cool facts like this..
And please comment if you like this post

                 TRAVELLING SALESMAN PROBLEM

INTRODUCTION :-
TSP is one of the most interesting 

problems of Operating System that 

haunts the beginners all the time . 

Reading from the book and 

understanding the TSP will take an 

entire day BUT with this simple post 

you will be able to get a clear picture of 

the problem in just two minutes .
JUST FOCUS FOR TWO MINUTES ....
WHAT IS TSP ?
 follow these steps ;-
     1. Imagine you are a salesman and 

your job is to go through a map 

consisting of 20 locations .
      2. your task is to visit each of these 

locations and to sell .
The KEY  POINT is to have minimize 

travelling time .....
you must be thinking how much time 

will it take .....
If  there are 3 locations  namely A , B , 

C  then following situations will arise 

:-
SITUATION 1 ->  Salesman will go to 

"A"  first , followed by "B "amd finally 

"C".
SITUATION 2 ->  Salesman will go to 

"B"  first , followed by "C "amd finally 

"A".
SITUATION 3 ->  Salesman will go to 

"C"  first , followed by "A "amd finally 

"B"
So ,choices left in the ways=>3*2*1 = 6
That means for 20 locations no. of ways 

 to be assessed are 20!= 

20*19*18.....2*1=2432902008176640000 ;
 which is gigantic and practically 

impossible to solve .
But there is a way to solve such 

problems which is GENETIC 

ALGORITHM that will give us an 

approximate solution but not an exact 

one.
GENETIC ALGORITHM SOLUTION =>
It is based on following two aspects -:
1. All locations to be visited .
2. All locations to be visited exactly 

once.
# G.A. solution comprises of MUTATION 

& CROSSOVER .
# MUTATION particularly SWAPPED 

MUTATION  used . In S.M. two values in 

d given location set are randomly 

chosen & swapped .EX - 
[ 1 2 3 4 5 ] =>[1 2 5 4 3 ]
Here 3, 5 are chosen and swapped 

among the location set.
It satisfies the above two aspects needed 

for valid solution . There will be no 

duplication and no missing of 

locations.
# ORDERED CROSSOVER which has 

the same foundations as S.M. and follow 

same constraints will be used here.See 

the following example -:
Parent gene - [1 2 3 4 5 (6 7 8 )9]
                   [9 8 7 6 5 4 3 2 1]
                     NOW =>
                  [ 9 5 4 3 2 6 7 8 1]
(After crossover).
This process is continued till the 

offspring has no empty values .
 If implemented correctly the end result 

should be a route which contains all of 

the positions it's parents did with no 

positions missing or duplicated.
THIS WAS THE SIMPLE G.A. SOLUTION 

FOR T.S.P .
FOR C-CODE OF THIS PROBLEM CLICK 

ON THE FOLLOWING LINK =>

http://www.theprojectspot.com

what the f**k is this? never expected from mashables.......

Did you noticed the puzzle by mashables??with the tag depicting Can you solve this super simple logic question that stumping on the internet??

if not then let me tell you the question..

in the figure given below there are six parking spots number,five are visible clearly just one is hidden because of a car,can you tell the hidden number within 20 seconds??

did you find the number??

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.

.

.

.

.

.

.

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.

.

.

.

.

.

.

.

anyone with a pretty common sense could tell that the answer is 87..

just flip the picture .

i didnt expected such a loose question from mashables...........

this is a f**king shit

Internet Connectivity Issue

There are often times when you are not able to connect your Laptop/Desktop to your wi-fi. You tend to think that your router is not working fine but it is not always the same. Following are the measures that has to be taken if router is working fine but you are not able to go online.You can use the following commands.

1. ping  the gateway of your router(here gateway means ip address of your router to access the router interface).If you are getting 0% loss then your gateway is connected to your computer.         
2. To check the internet connectivity either you can ping "4.2.2.2" or you can ping any website ex"ping www.google.com",if you get 100% loss it means internet is not working and in that case you need to check your router .
3. To check whether the network adapters of your computer is working or not you can use loop back command, The syntax for the command is : "ping 127.0.0.1" (this is the default address of every network adapter). If you are getting 100% loss then the adapter of your system is not working.
   

google maps latest update tell whether the place you are heading is closed or open

It happens often you are late from office and then decide to go somewhere to grab a drink,for dinner or for shoppong and on reaching that place you find it closed. Thats really frustrating.But dont worry now google maps latest update brings you solution for that.The new google maps update will tell you time schedule for anystore bar or restaurant.If you searched to locate any place from google maps then it will not only tell you route and estimated time to reach but also flag it up if that place is already closed or will be closed till the time of arrival.

google always trying to find a solution to make life of their users comfortable.

cryptography basics part iv

COMPOSITION OF CIPHERS

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In previous articles of cryptography we learnt how to encrypt a text using block substituted ciphers and transposition ciphers.these are good ciphers to a noob but these ciphers are cakewalk for a man having appreciable knowledge of cryptography.so let us make our ciphers even harder to crack using composition of ciphers.
so what really is composition of ciphers?? it is nothing but making a harder cipher using ciphers we already know.Double columnar cipher which we learnt in previous section is an example of this approach.
First let us apply this for block substituted ciphers.we learnt monosubstituted cipher and polysubstituted cipher.let us try to combine both the ciphers.
let us take the example "WELCOME TO FREE LEARN HACKING"

1. write the text in the blocks of length 5 "WELCO METOF REELE ARNHA CKING "
2. first applying key for polysubstituted cipher take key as replace first alphabet by its first successor,second alphabet by its second successor,third alphabet by its third successor,fourth alphabet by its fourth successor,fifth alphabet by its fifth successor
   our encrypted text will become "XGOGT NGWSK SGHPJ BTQLE DMLRL"
3. Now apply monosubstituted cipher ,deciding our key as replace each alphabet with their second successor like A from C
   now our text will become "YHPHU OHYTL JHIQK CURMF ENMSM"

This our new secret code and believe on me it is better than previous one.

Now let us experiment for route ciphers and columnar transposition cipher.we will be first performing route cipher and then columnar transposition

1. let us take the example "WELCOME TO FREE LEARN HACKING"
2. write the text in the blocks of length 5 "WELCO METOF REELE ARNHA CKING "
3. now we will apply route cipher therefore write in form according to the figure given below
   
4. now the encrypted text becomes WMRAC KINGA EFOCL EEERN HLOTE
5. now applying transposition cipher we get "WMRAC EEERN KINGA HLOTE EFOCL"
our new crypted text.

hey isnt it great forming powerful ciphers from existing ciphers we already know. we can also make composition of transposition cipher and substituted cipher, any permutation in your mind could result in a new cipher.

print counting in c++ without using loop,recursion and goto

can you write a code for printing counting without using loop,recursion,goto statement?

hey everyone who likes to code has written a code in c++ for coding.also everyone has designed a code for printing counting 1 to 100. but can you design a code for printing counting without using loop,recursion and goto statement?
The one answer could be simply printing 1 to 100 using cout statement but that's not a coder's answer.
the one could be using class and the code is written below

interesting isnt it??
there are more alternatives ways, try to design one of your own
bbye... and stay tuned for more such interesting posts......

Fuzzy sets Operation

                   FUZZY  SET  OPERATIONS :
1. FUZZY  UNION :-
         A = {( x , 0.5) , (y , 0.7) , (z ,0)}  

          B={( x , 0.8) , (y , 0.2) , (z ,1)}
A U B = A UNION B
         = maximum of membership       
     degree among the sets
A U B = ( x , 0.8) , (y , 0.7) , (z ,1)}
 NOTICE -
          0.8 > 0.5
           0.7 > 0.2
            1 > 0

2. FUZZY  INTERSECTION :-
 A = {( x , 0.5) , (y , 0.7) , (z ,0)}         B={( x , 0.8) , (y , 0.2) , (z ,1)}
 A INTERSECTION B  = minimum of
membership degree among the sets
= ( x , 0.5) , (y , 0.2) , (z ,0)}

 NOTICE - 
          0.8 < 0.5
           0.7 < 0.2
            1 < 0

3.  A ' = COMPLEMENT OF A
A = {( x , 0.5) , (y , 0.7) , (z ,0)}         B={( x , 0.8) , (y , 0.2) , (z ,1)}
A ' = 1 - MEMBERSHIP DEGREE
A ' = {(x , 0.5), (y ,0.3) , (z,1)}
B ' ={(x , 0.2) , (y,0.8) , (z,0)}

4.  A - B = ? 
A = {( x , 0.5) , (y , 0.7) , (z ,0)}        
B={( x , 0.8) , (y , 0.2) , (z ,1)}
A - B = A INTERSECTION B'
         = minimum of membership       
     degree among the sets
A- B = {(x , 0.2) , (y , 0.7) , (z ,0)}

5. POWER OF  FUZZY SET = ? 
   IF "A " IS A FUZZY SET THEN
     POWER SET (A)  =  (membership
degree of set )^ $
       P(A) = (M. DEGREE)^$
NOTE -
        IF $ = 1/2 THEN IT IS CALLED
"DILATION"
       IF $ = 2 THEN IT IS CALLED
"CONCENTRATION "

EXAMPLE - 
A = {( x , 0.5) , (y , 0.7) , (z ,0)} 
$ = 2
A = {( x , 0.25) , (y , 0.49) , (z ,0)} 

Play with fuzzy sets

 PLAY WITH  FUZZY  SETS :

A set or a crisp set is defined  as a 

collection of elements . The elements are 

either a member or not a member of the 

set . But Fuzzy sets are more flexible in 

approach  as compared  to the sets .

Fuzzy set can be viewed as an 

extension & generalization 0f  the 

basic concepts of crisp set .It supports 

flexible sense of membership with a 

parameter called "membership  degree" . 

It is multivalued between 0 and 1 (both 

included). You  will be  surprised  to 

know that Fuzzy logics donot follow 

LAW  OF EXCLUDED MIDDLE & LAW 

OF CONTRADICTION .If  we will choose 

fuzzy union & intersection that will 

follow these law then , the operations 

will not satisfy distribution and 

idempotence .

LAW  OF EXCLUDED MIDDLE states 

that for any proposition , either that 

proposition is true , or its negation is 

true .
LAW  OF CONTRADICTION  states that 

two antiethical propositions cannot be 

true at the same time . For example - X 

cannot be NOT X simultaneously.
Distributive property :-
                        5(x+30) = 5x + 150 
Idempotence property :-
                          op( op(x)) == op(x)

cryptography basics part iii

CRYPTOGRAPHIC BASICS PART III

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In previous article we learnt about classification of cipher codes and then detailed analysis of two types of block ciphers maonosubstituted block cipher and polysubstituted block cipher.
The one not following my cryptography posts reading for first time must took a glance at older posts by the link given below
cryptographic-basics-part-i
cryptography basics part ii
today we will look to another type of block cipher known as transposition cipher,
Transposition cipher:It follows method of encryption by which position of simple text are shifted according to a regular pattern to form cipher text.
We will discuss three types of transposition ciphers here

• route cipher:let us take the example "WELCOME TO FREE LEARN HACKING"
  
  1. write the text in the blocks of length 5 "WELCO METOF REELE ARNHA CKING "
  2. now write in form according to the figure given below
     
  3. now the encrypted text becomes WMRAC KINGA EFOCL EEERN HLOTE
• columnar transposition:

we will use the same text "WELCOME TO FREE LEARN HACKING"

1. write the text in the blocks of length 5 "WELCO METOF REELE ARNHA CKING "
2. now write in form given below
   1 3 5 2 4
   W M R A C
   E E E R K
   L T E N I
   C O L H N
   O F E A G
3. now we have to chose a key suppose we chose our key as "CRYPT" then we will mark it in ascending order C-1 P-2 R-3 T-4 Y-5 whichever occurs first in alphabets
4. now the encrypted text becomes WMRAC COLHN EEERK OFEAG LTENI

double columnar transposition:

here we will repeat the same task two times we will use the same text "WELCOME TO FREE LEARN HACKING"

1. write the text in the blocks of length 5 "WELCO METOF REELE ARNHA CKING "
2. now write in form given below
   1 3 5 2 4
   W M R A C
   E E E R K
   L T E N I
   C O L H N
   O F E A G
3. now we have to chose a key suppose we chose our key as "CRYPT" then we will mark it in ascending order C-1 P-2 R-3 T-4 Y-5 whichever occurs first in alphabets
4. now the new text becomes
   1 3 5 2 4
   W M R A C
   C O L H N
   E E E R K
   O F E A G
   L T E N I
5. Now we will again apply the key crypt in the same manner
6. our encrypted text become WCEOL AHRAN MOEFT CNKGI RLEEE

There are hundreds of types of transposition cipher available.you can also make your own transposition cipher but it should be logically correct.
Transposition ciphers prove to be better cipher than substitution cipher
In next article we will be getting knowledge of more different powerful techniques.

cryptography basic part II

CRYPTOGRAPHIC BASICS PART II

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In earlier article we learnt about functions .
today we will be messing our hands in real stuff,encryption with primitive methods
The one not following my cryptography posts reading for first time must took a glance at older posts by the link given below
cryptographic-basics-part-i
Basically encrypyion and decyption is done by the use of a key,which is designed by encryptor to encrypt it.
Basically key is divided in two broader categories

• Symmetric key
• Public Key

In this article we will focus on symmetric keys
Symmetric keys have been used ancient times so it has a wide history,Ancient greeks ,ancient egyptians used it,But the most recognised incident is the use of symmetric keys by nazis during world war II with the help of Enigma machine,Enigma was considered as an uncrackable machine.Had not been there the great cryptanalyst Alan Turing,British would have suffered a lot.

Symmetric key:the key used for encryption and decryption is same rhe actual text and ciphered text are easily convertble function. Once a cryptanalyst knew the original key used for encrypting the text he could easily decrypt the ciphered text.therefore the key used should be kept secret and passed through secured channel while the ciphered text could easily passed through unsecured channel.

Symmetric Keys too are classified in two other broader categories

• Block ciphers
• Stream ciphers

Block ciphers : these ciphers encode the text to a block of fixed length and then precede according to key

here we will discuss only substituted block ciphers
there are two kinds of substituted ciphers:

• monosubstituted cipher
• polysubstituted cipher

Monosubstituted cipher:this encode using a single pattern for key,for example:
let us encode the text according to monosubstituted block cipher
Our text is "WELCOME TO FREE LEARN HACKING"
we will follow the steps:

1. first make block of fixed length for text say 5
   then our text will become WELCO METOF REELE AENHA CKING
2. now comes the crucial step deciding the key,let us decide the key as replace each alphabet with their second successor like A from C
   now our text we look like YGNEQ OGVQH TGGNG CTPTC EMKPI

Bravo you have encrypted your first code...

Polysubstituted ciphers: in this we follow different pattern for text for each position at the code block,for example let us encode the same text used above using polysubstituted block cipher
Our text is "WELCOME TO FREE LEARN HACKING"
we will follow the steps:

1. first make block of fixed length for text say 5
   then our text will become WELCO METOF REELE AENHA CKING
2. now comes the crucial step deciding the key,let us decide the key as replace first alphabet by its first successor,second alphabet by its second successor,third alphabet by its third successor,fourth alphabet by its fourth successor,fifth alphabet by its fifth successor
   now our text will look like XGOGT NGWSK SGHPJ BTQLE DMLRL

Polysubstituted cipher is much hard to crack in compariso to monosubstituted cipher...
we will learn some more powerful ciphers in next article till then keep on making ur information secretive using these ciphers

cryptography basic

CRYPTOGRAPHY BASICS

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What is cryptography?
cryptography is art of changing any simpler text to a secret code.so how are hacking and cryptography related?hacking is simply gaining access to any system,while the work of cryptography is to encode a simpler text to secret code to provide confidentiality and information security.having knowledge of cryptography helps to make our system more secure.

cryptography is study dealing with mathematics and computers both.so to achieve command on it we have to learn some basic mathematics.
lets catchup some information regarding functions..

what is functions?
let us take Y as a function of X
Domain:the values which is given as input
Range:the values which came as output
So elements in X constitutes domain,and elements in Y which are also called as image constitute range
it is a relation satisfying the below conditions
1.Each element of X should have one image in Y
2.No element in X could have two or more corresponding values in Y
3.Y could have one or more than one values of X
4.It is not mandatory that each element in Y should have corresponding X.

Bijective funtions:functions in which each element in X has only one image in Y and no element in Y should be empty

Inverse function:If Y is made to be codomain then X will automatically become image of Y if the function is bijective function, otherwise inverse of a function is not possible

Trapdoor one way functions:They are the most important type of functions for cryptography.By definition one way function is that function whose inverse is hard to find unless some very essential information is given which is called trapdoor.so for now only we will keep ourselves reserve with this definition only and will exploit trapdoor functions in our next topic