Problem 42525. Vigenere cipher - be like Sherlock Holmes!

Created by mawlndjr xslkveal

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You're a young detective. Every detective needs a function to decrypt a vigenère cipher. It's a modification of a caesar cipher.Let's talk more about the algorithm:<ul><li>Every letter is a number. A=0, B=1, C=2, (...), Z=26</li><li>Output should be presented in capital letters.</li><li>Use ONLY letters. Without interpunction, spaces, etc</li><li>Function has two arguments: encrypted text and key (both are strings). Your output will present a decrypted text. Let's show it on easy example from <a href = "http://en.algoritmy.net/article/45623/Vigenere-cipher">http://en.algoritmy.net/article/45623/Vigenere-cipher</a></li></ul>Ciphertext : CTMCCD, Key : CatC – C = 2 – 2 = 0 = AT – A = 19 – 0 = 19 = TM – T = 12 – 19 = 19 = TC – C = 2 – 2 = 0 = AC – A = 2 – 0 = 2 = CD – T = 3 – 19 = 10 = Kdecrypted word: ATTACKIt's quite simple,right? Good luck!<a href = "http://en.algoritmy.net/article/45623/Vigenere-cipher">You can read more about this cipher here. Click!</a>

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78 Solutions
26 Solvers

Last Solution submitted on Mar 29, 2023

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daniel lamont on 21 Aug 2015

you should add a test case like GrantII does in his 'divisible by X' problems...
http://www.mathworks.com/matlabcentral/cody/problems/42408-divisible-by-6

mawlndjr xslkveal on 21 Aug 2015

thanks for advice! done! :)

Peng Liu on 21 Aug 2015

Your testsuite is still incomplete. I recommend you to include cases where Ciphertext and Key both contain upper and lower case letters

Peng Liu on 21 Aug 2015

Please kindly note that your test case 3 (a='az' b='za' y_correct='zz') is wrong. If you re-score all solutions, I think none of them would pass this test case. However, you may need to re-score multiple times because ind = randi(3) does not necessarily yield ind = 3.

mawlndjr xslkveal on 21 Aug 2015

thanks, I missed that mistake. it should be ok right now.

Christian Schröder on 30 Oct 2022

"A=0, B=1, C=2, (...), Z=26"

Shouldn't Z be 25?

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Solution 719322

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mawlndjr xslkveal on 21 Aug 2015

cheater. what's the point of doing that?

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Problem 42525. Vigenere cipher - be like Sherlock Holmes!

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