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Now, coming back to our transposition encryption algorithm, so let's go back to over Demo 10 over

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here.

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Now we're going to use the list in our acceptable encryption algorithm to create a ciphertext ASTRAEA

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over here.

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We're going to see the ciphertext estar open the list multiplied by the year.

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Now, each string in the ciphertext Asgeir variable represents a column of the transpositions Saiful

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grid because number of column is equal to the key.

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You can use this replication to multiply a list with one blank string value in it by the by value in

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a particular key.

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So the string values will be assigned.

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All the characters that go into one column of the result will be the list of string value that represents

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each column as discussed earlier.

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Now, because the list indexes starts with zero, you will need to also label each column starting at

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zero.

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So you'll receive ciphertext zero or ciphertext Asgeir zero is the leftmost column and ciphertext ETR.

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One is the column to the right of that particular column and so on and so forth.

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So over here, the next step here will be adding the text to each string in the ciphertext.

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Asgeir as just did it as an example.

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Except this time we will add some code to make the computer do it programmatically.

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So here we are looping it through the foreach loop.

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So we are seeing four columnist here in the range of Gasteyer current ideas is equal to the columnist.

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So over here we are looping or iterating once for each column and the column variable has an integer

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value to use for the indexes to ciphertext Asgeir on the fourth iteration through the for loop.

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The column is still variable, set to zero on second set to one and so on.

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We have an index for the string values in the ciphertext Asgeir that we want to access later using the

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expression ciphertext Asgeir in the index of columnist.

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Now meanwhile, the current index variable who is the index of the message string for the program,

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looks at on each iteration for the loop, on each iteration the same or the current index of the same

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value as columnist and I will create a ciphertext ETR concatenating the scrambled the message together,

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one character at a time succumbing to the argument that assignment operator is not so far that we have

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concatenated or added values to each other.

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We have used plus operator to add a new value to the variable.

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Often when you're assigning a new value to a variable, you want it to be based on the variables current

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value.

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So you need to use variable as a part of the expression that is evaluated and assigned to a variable.

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For example, if you try to enter something in the interactive shell here like C span, that's equal

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to say 30 and here we say Hispanic will do span plus four and then we say put in the Valley of Spath,

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we get that thirty four printed.

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Now there are other ways to manipulate values in the variables based on the variables, current value.

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For example, you can do this by using the argument that assignment operators, the statement like for

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example, spane plus equal to two, which is used as plus equal to argument and assignment operator

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does the same thing as is equal to spend plus two, something like that.

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Right.

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So just a little shorter to type it.

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So the plus is equal to operator Volks with integers to do additions, strings to do string concatenation

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and less to do a list concatenation.

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So if we go back to our program here, they're more ten now over here.

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The value that this we have used to ciphertext Stia.

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So over here, the variable that is your current idea is basically holding the index of the next character

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in the message string.

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Now that will be concatenated to your ciphertext estar list.

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And the key added to the current index on each iterations will be to the point two different characters

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in the messages to you.

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And in each iterations, the current idea is set to the value and the columnist.

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You are variable to scramble the string in the message variable.

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We need to take the forced character of the message that is over here p and put it into the four string

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of the ciphertext STF.

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Then we will keep eight characters in the message because the key is equal to eight and concatenate

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the character that is after eight to do four string of the ciphertext estimate, we will continue to

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skip characters according to the key and concatenate each character until we reach the end of the message.

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Not doing so would create a particular string that we have forced us.

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We have getting there the value that this Sipi then if you just look at the excel that we have here

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and it's B always this default.

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The string that would be getting, which is the fourth column of the ciphertext year, then we would

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do this again, but started the second character in the message to make the second column.

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So inside the for loop that we have in our particular program available, that starts on the particular

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next line over here.

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It concatenated they write characters in the message to make each column and it loop wildly.

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Current idea is less than the length of the message now for each column, the how it reads through the

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original message variable and picks out the characters in the intervals of the key by adding to the

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current idea.

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OK, so after the break you have the message Estado all messages during the bracket in current IDEX

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is the false character of the message of the particular first iteration and the character at the message.

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Current IdeaCast is concatenated to the cipherText SDR column to start the first column in the next

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line.

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So in this way, the fourth time, the message zero second time with this message eight and third time

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with this message 16, four time with this message.

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Twenty four.

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That is how we get all the particular values concatenated.

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So although the value of the current idea is less than the length of string, but when you continue

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concatenating and the characters to the end of the string, add the column index is ciphertext Asgeir.

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When the current index is greater than the length of the message, execution will stop there.

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And because that isn't good indeed for block after the value, the loop or the for loop iterates column

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and sits at the one and the current index starts at the same value as the column.

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So over here we will get the values that we have got through the Manual V as we have created.