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Welcome to the next session in our Biton hacking class that is programming a program to test your particular

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program.

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So now here, the transposition program seems to work pretty well at encrypting and decrypting different

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messages with various keys.

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But how do you know?

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They always will?

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Now, you cannot be absolutely sure the program always work unless you test the encrypt message and

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the decrypt message functions with all sorts of message and keep it amateur values.

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But this will take a lot of time because you would have to type a message in an encryption program,

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said Thuggy.

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Run the encryption program then based ciphertext into the decryption program, said the key, and then

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run the decryption program.

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You would also need to repeat that process with several different keys and messages, resulting in a

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lot of boring work.

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Now, instead of this, we can write down another program that can generate a random message and a random

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key to test the cipher programs.

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Now these programs will encrypt the message using the encrypted message matter and then pass that particular

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ciphertext to your decrypt message matter.

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And if a plain text written by the decrypt message the same as the original message, then the program

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will know that the encryption and the decryption program have voted no.

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The process of testing a program automatically using another program is called the Automated Testing.

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Now several different messages and key combinations need to be tried, but it takes the computer only

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a minute or so to test thousands of combinations.

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So if all those test pass, then you can be more certain that your code has locked it.

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Now to the cover this particular session, which would be also covering the random go round end function,

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the random seed function.

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We will also see what are different types of list of references.

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We will cover the copied or deep copy functions, random code shuffle function, randomly scrambling

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a particular string and system exit function.

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OK, so now we would come for writing down a particular code for testing our transposition program.

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So here we would go for a new file and we would type.

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First thing we required is import random.

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Then since then trons position encrypt and

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transposition decrypt.

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Now we would be defining the main method here.

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Inside this, let us use the random dot seed function and here we are giving sailele static value for

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you.

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Now this is, we have said the random C to a static value that we have set it here, not below this.

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We would run a for loop which will go in a range.

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And between 20, so we're basically going to run 20 test for this encryption and decryption process,

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so this will generate some random messages which will be helpful for us to testing.

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And then if you go inside the for loop here, we would create a single message SDR that is equal to

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let's give some capital numbers.

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So g h i j k l and if you want Rusty, you've W, X, Y and Z.

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Now we have given everything into capital.

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Then here we say multiply multiplied by random dot.

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Decline in function, but we are passing for coma for now, this message that we have created will also

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have a random length for that length.

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We have defined it over here after this.

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In the next line, we would say same message as we will do list in bracket message, as are now.

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He'll be able to convert the message Asgeir string to a list which will be basically used to shuffle.

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And then after this we would use the random dot shuffle function.

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And in this also we would pass the message STF now after we have shuffle this, we will create a message

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as hour is equal to blank, then dot join and again, let's give your message Asgeir.

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Now this is basically used to convert the list back to string and then don't forget to give up command.

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Here we are giving the best hash we put into your 10 percent as colon double code as close this single

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code, give your bracket five plus one comma.

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The value of message estie are all 50 in square brackets and let's close the round bracket.

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Now, after this, we will have to check for all the possible keys for each message.

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So for that we would go for 60 are in our range.

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We are giving you starting from one and converting it to integer.

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The length of your message, Estie, are divided by two.

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And after this, let's create your.

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So encrypted a that's equal to now.

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Here we are going to use the transposition, say, transposition and grip dot.

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We will use the encrypted message method and we will pass here.

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The key is here and the message is still whatever the value will be written will be stored in this encrypted

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Ostia.

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Similarly, here, we will use decrypted Ostia.

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That's equal to psytrance position.

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Use the decrypt, not decrypt message.

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And again, helth will use the key here.

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But now for decrypting, it will have to pass the value that this encrypted SD card here does so that

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the same encrypted text would be again decrypted.

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So if the decryption doesn't match the original message, we have to display an error message and we'll

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have to quit.

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So now after this, we will have to go for another safe.

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Checking for the message.

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Astarte, if that is not equal to your decrypted SDR, then what are you supposed to do?

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We will give your opponent saying, say, mismatch with GISTARO percent s and message SDR wasn't as

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Clouzot and put into the values of still comma messages dear after this Nibelungen print.

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Another saying the decrypted US Colen close this and printed the value of decrypted STF.

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And after this we would say Stop it.

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Now, once this is done, the next thing we'll have to do is let's come out of this and move back in

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the for loop.

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Here and here, we would be printing see the transposition cipher text has passed successfully.

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That will be the end of this particular session that we have defined the main method.