Crypto Columns The columnar encryption scheme scrambles the letters in a message (or plaintext) using a keyword as illustrated in the following example: Suppose BATBOY is the keyword and our message is MEET ME BY THE OLD OAK TREE. Since the keyword has 6 letters, we write the message (ignoring spacing and punctuation) in a grid with 6 columns, padding with random extra letters as needed: MEETME BYTHEO LDOAKT REENTH Here, we've padded the message with NTH. Now the message is printed out by columns, but the columns are printed in the order determined by the letters in the keyword. Since A is the letter of the keyword that comes first in the alphabet, column 2 is printed first. The next letter, B, occurs twice. In the case of a tie like this we print the columns leftmost first, so we print column 1, then column 4. This continues, printing the remaining columns in order 5, 3 and finally 6. So, the order the columns of the grid are printed would be 2, 1, 4, 5, 3, 6, in this case. This output is called the cipher-text, which in this example would be EYDEMBLRTHANMEKTETOEEOTH. Your job will be to recover the plain-text when given the keyword and the cipher-text. Input There will be multiple input sets. Each set will be 2 input lines. The first input line will hold the keyword, which will be no longer than 10 characters and will consist of all uppercase letters. The second line will be the cipher-text, which will be no longer than 100 characters and will consist of all uppercase letters. The keyword THEEND indicates end of input, in which case there will be no ciphertext to follow. All input will be from a file: input.dat Output For each input set, output one line that contains the plain-text (with any characters that were added for padding). This line should contain no spacing and should be all uppercase letters. All output will be to the screen Sample Input BATBOY EYDEMBLRTHANMEKTETOEEOTH HUMDING EIAAHEBXOIFWEHRXONNAALRSUMNREDEXCTLFTVEXPEDARTAXNAARYIEX THEEND Sample Output MEETMEBYTHEOLDOAKTREENTH ONCEUPONATIMEINALANDFARFARAWAYTHERELIVEDTHREEBEARSXXXXXX CODE IN PYTHON AND COMMENT TO EXPAIN THE PROGRAM
Crypto Columns
The columnar encryption scheme scrambles the letters in a message (or plaintext) using a keyword as illustrated in the following example: Suppose BATBOY is the keyword and our message is MEET ME BY THE OLD OAK TREE. Since the keyword has 6 letters, we write the message (ignoring spacing and punctuation) in a grid with 6 columns, padding with random extra letters as needed:
MEETME
BYTHEO
LDOAKT
REENTH
Here, we've padded the message with NTH.
Now the message is printed out by columns, but the columns are printed in the order determined by the letters in the keyword. Since A is the letter of the keyword that comes first in the alphabet, column 2 is printed first. The next letter, B, occurs twice. In the case of a tie like this we print the columns leftmost first, so we print column 1, then column 4. This continues, printing the remaining columns in order 5, 3 and finally 6. So, the order the columns of the grid are printed would be 2, 1, 4, 5, 3, 6, in this case.
This output is called the cipher-text, which in this example would be EYDEMBLRTHANMEKTETOEEOTH.
Your job will be to recover the plain-text when given the keyword and the cipher-text.
Input
There will be multiple input sets. Each set will be 2 input lines. The first input line will hold the keyword, which will be no longer than 10 characters and will consist of all uppercase letters. The second line will be the cipher-text, which will be no longer than 100 characters and will consist of all uppercase letters. The keyword THEEND indicates end of input, in which case there will be no ciphertext to follow.
All input will be from a file: input.dat
Output
For each input set, output one line that contains the plain-text (with any characters that were added for padding). This line should contain no spacing and should be all uppercase letters.
All output will be to the screen
Sample Input
BATBOY
EYDEMBLRTHANMEKTETOEEOTH
HUMDING
EIAAHEBXOIFWEHRXONNAALRSUMNREDEXCTLFTVEXPEDARTAXNAARYIEX
THEEND
Sample Output
MEETMEBYTHEOLDOAKTREENTH ONCEUPONATIMEINALANDFARFARAWAYTHERELIVEDTHREEBEARSXXXXXX
CODE IN PYTHON AND COMMENT TO EXPAIN THE PROGRAM
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