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caesar_cipher

Language/Type: Python string interactive programs

Write a complete console program that implements a Caesar cipher or rotation cipher, which is a crude system of encoding strings by shifting every letter forward by a given number. Your program should prompt the user to type a message and an encoding "key" (number of places to shift each character) and display the shifted message. For example, if the shift amount is 3, then the letter A becomes D, and B becomes E, and so on. Letters near the end of the alphabet wrap around for a shift of 3, X becomes A, and Y becomes B, and Z becomes C. Here are two example dialogues: 

Your message? Attack zerg at dawn
Encoding key? 3
DWWDFN CHUJ DW GDZQ

Your message? DWWDFN CHUJ DW GDZQ
Encoding key? -3
ATTACK ZERG AT DAWN
Complete program: Write an entire program that you could put into a file and run outside of CodeStepByStep.

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