2.3, due on September 10

The Interesting 

When I came up with the method for coding our message for our homework project, I thought I had been totally original and completely tricky. I am so surprised to find out that this same method is already invented and just in chapter 2-- it was the vigenere cipher! I thought that was really cool. 

The Difficult

I think the hardest part of this section is understanding how the book was using dot products to theorize about solving for the key. I couldn't follow what they were doing with the vectors and the code and how they connected in 2.3.2 but they based their explanation of 2.3.3 off of it, so I didn't understand how the second method for finding the key worked either.