Python 3: String Methods: Coded_Correspondence project: Step 5

[thevizslacoder]

Please help me understand the Vigenere Cipher in the Coded_Correspondence project? I am frustrated with myself for not only NOT understanding how this cipher works, but also not understanding how any of the code solutions given to me make sense. Link below …

https://www.codecademy.com/courses/learn-python-3/informationals/python3-coded-communication

In the screenshot below, you’ll see that I found the index of the message letter (in blue) and added it to the index of the keyword phrase letter (in red) which equalled a number that I thought was the index value (resulting place value) of the letter in code (pink). My first two resulting place values matched the example that was given to us. But my third and fourth letters had index values of 23 (for letter x) and 20 (for letter u) which matched the same letters as the example give to us … but did not match the resulting place values of 15 or 12. I don’t understand what I did wrong here?

[janbazant1107978602]

I think the example shown is wrong after the first 2 letters, but your computations are correct.

[thevizslacoder]

Thank you janbazant. I spent a good hour or so trying to figure out where my thinking was off… Someone on the Codecademy staff please fix the mistake so that others don’t waste time and get discouraged like me!