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Welcome to the first session in a row by phone hacking, intermediate level court now in the last course

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of in the last session, we have used the transpositions file Saiful to encrypt and decrypt the entire

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file, but we haven't tried writing a brute force program to decipher no messages encrypted with the

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transposition file.

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A cipher can have thousands of possibilities, which your computer can still easily brute force, but

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you would then have to look through thousands of descriptions to find the one correct plaintext.

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Now, as you can imagine, this can be a big problem.

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But there is a workaround for this.

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When the computer decrypt the message using the Ronke, the resulting string is garbage text.

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Instead of a normal English text, we can basically programmed the computer to recognize when or decrypted

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messages English that we if the computer decrypts using the Ronke, it goes on and tries the next possible

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case.

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Eventually when the computer dries up the decrypts to English text, it can then stop and bring that

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to your attention, sparing you from having to look through thousands of incorrect descriptions.

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So basically, let us see, how can a computer understand English?

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Now, basically a computer can't understand English, at least not in the way that human beings understand.

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Now, computers don't understand even math, chess or human rebellion's either any more than a clock

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understands lunchtime.

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So computer just executes the instructions one after another.

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But these instructions can mimic complex behaviours to solve the math problems when the chips are down.

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The future leader of a human resistance.

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Ideally, when we need to create a python function, for example, is English function.

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That is, we can pass a string to it and get a written value through if the string is English or force

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if it's some random or gibberish in that particular case.

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So let us look at some English text and some garbage text to see what patterns they might have.

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Now, for example, if we type something like C Python's R.

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Your friends, OK, or if you type something like instead of this.

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Now, this is not what a human can read, right?

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I notice that the English text is basically made up of words that you would find in a dictionary, but

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the garbage text isn't because votes are usually separated by spaces.

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One way of checking whether a message string is English is to split the message into smaller strings

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at each space and check whether each string is a dictionary word to split the message string into some

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strings.

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We can use the python string method name that is split when checks where each word begins and ends by

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looking for spaces between the characters.

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Right now we can then compare each substring to each word in the dictionary using an if statement.

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OK, now we would all like that.

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We would probably wouldn't because it would be tedious to type all of it.

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And fortunately we can use the English dictionary files, which are basically text files that contain

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nearly every word in English that basically will provide you with a dictionary file, which you can

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use.

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So we just need to write down the function.

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For example, it is English function that checks without a substring is a message or a particular substance

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available in the messages are in a dictionary file.

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So not every word exists in our dictionary.

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Dictionary files might be incomplete.

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For example, it might have the word names it all, but there are some perfectly good descriptions that

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might have non English words in there, like, for example, Xavi w six eight six in s, for example,

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like this.

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OK, so a plain text could also be in a different language, but will assume it's in English now.

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So we would write down it is English function.

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OK, that won't be foolproof obviously, but we will give it a try.

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And now there is a low probability that a ciphertext that is decrypted using the Ronke will decrypt

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to English.

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OK, now first thing is we will download a dictionary file for this which we already have created.

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And it's basically a text file which is having one word for line in the uppercase.

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OK, now we would just add it or and I'll show you after opening it.

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All votes do we have.

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So let's remove it.

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Now, if you go to a drive, we have a folder as an intermediate level where we have created this dictionary

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file, which is having one more power line, all in capital, having some English words stored in the

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file.

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This is basically able to find them dictionary dot the exchange.

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Now, we would create a function named is English OK, which will basically split a decrypted string

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into individual sub strings and check whether each substring exist as a word in the dictionary.

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And if a certain number of such strings of English words will identify that text as English, and if

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the text is in English, there's a good chance that will have successfully decrypted a ciphertext with

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the correct.

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So now we would write down the source code for the English module.

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OK, we'll create a new file and write down the code and do it.

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OK, so we will create file new file and we will create Sea of Letters this year and we will give all

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the letters and packages a, b, c, d, e, f, g, h, i, j, k, l.

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And many of you oreste, youve w, x, y, z.

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After this, we would create another constant letter and space esteve and that is equal to we have this

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little S.T. are with this.

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We would concatenate the upper little estie are dot the lowercase characters, all of this.

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Plus we would give a space slash D and new line also on all we would concatenate in letters and space.

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Then we would define a function.

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Now, that is our see law victory and that is Law Dictionary, and in this function, the first thing

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we would create is a dictionary file.

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And here we would use open and we would give that file, that is.

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Dictionary dot, the 60, the one which we have right now, created and saved in the same folder where

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we are able to see the current fight.

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So after giving this here, we will create the English votes SDR is equal to initially it is blank.

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We create for World One in our dictionary file, SDR dot read dot split using a slash and because on

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one line we are having one vote.

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So we are splitting it whenever we find a new line.

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And in that we are seeing English votes as are in the index of vote one, we are saving the value was

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none initially.

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OK, then we see a dictionary file is still not close and we are returning here and the value of English.

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Revolt's still and we end this function here and then we see the English votes.

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Our vote is equal to we are calling the law dictionary method that we have created.

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So that will get stored in a constant name, English word estopinal.