70 http://inventwithpython.com/hacking
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THE CAESAR CIPHER
Topics Covered In This Chapter:
The import statement
Constants
The upper() string method
for loops
if, elif, and else statements
The in and not in operators
The find() string method
“BIG BROTHER IS WATCHING YOU.”
“1984” by George OrwellImplementing a Program
In Chapter 1, we used a cipher wheel, a St. Cyr slide, and a chart of letters and numbers to
implement the Caesar cipher. In this chapter, we will use a computer program to implement the
Caesar cipher.
The reverse cipher always encrypts the same way. But the Caesar cipher uses keys, which encrypt
the message in a different way depending on which key is used. The keys for the Caesar cipher