Python Programming: An Introduction to Computer Science, 3rd Ed.
3rd Edition
ISBN: 9781590282755
Author: John Zelle
Publisher: Franklin, Beedle & Associates
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Question
Chapter 5, Problem 7PE
Program Plan Intro
Program to encode and decode caesar cipher
Program plan
- Inside the “main()” function,
- Declare “plaintext” and “key” and get input from the user.
- Declare “ciphertext” and then encode the plaintext into ciphertext.
- Print the encoded message.
- Call the “main()” function.
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A Caesar cipher is a simple substitution cipher based on the idea of shiftingeach letter of the plaintext message a fixed number (called the key) ofpositions in the alphabet. For example, if the key value is 2, the word"Sourpuss" would be encoded as "Uqwtrwuu." The original message canbe recovered by "reencoding" it using the negative of the key.Write a program that can encode and decode Caesar ciphers. The input to the program will be a string of plaintext and the value of the key.The output will be an encoded message where each character in the original message is replaced by shifting it key characters in the Unicode character set. For example, if ch is a character in the string and key is theamount to shift, then the character that replaces ch can be calculated as:chr (ord(ch) + key) .
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Simple python program
Chapter 5 Solutions
Python Programming: An Introduction to Computer Science, 3rd Ed.
Ch. 5 - Prob. 1TFCh. 5 - Prob. 2TFCh. 5 - Prob. 3TFCh. 5 - Prob. 4TFCh. 5 - Prob. 5TFCh. 5 - Prob. 6TFCh. 5 - Prob. 7TFCh. 5 - Prob. 8TFCh. 5 - Prob. 9TFCh. 5 - Prob. 10TF
Ch. 5 - Prob. 1MCCh. 5 - Prob. 2MCCh. 5 - Prob. 3MCCh. 5 - Prob. 4MCCh. 5 - Prob. 5MCCh. 5 - Prob. 6MCCh. 5 - Prob. 7MCCh. 5 - Prob. 8MCCh. 5 - Prob. 9MCCh. 5 - Prob. 10MCCh. 5 - Prob. 1DCh. 5 - Prob. 2DCh. 5 - Prob. 3DCh. 5 - Prob. 4DCh. 5 - Prob. 5DCh. 5 - Prob. 1PECh. 5 - Prob. 2PECh. 5 - Prob. 3PECh. 5 - Prob. 4PECh. 5 - Prob. 5PECh. 5 - Prob. 6PECh. 5 - Prob. 7PECh. 5 - Prob. 8PECh. 5 - Prob. 9PECh. 5 - Prob. 10PECh. 5 - Prob. 11PECh. 5 - Prob. 12PECh. 5 - Prob. 13PECh. 5 - Prob. 14PECh. 5 - Prob. 15PECh. 5 - Prob. 16PE
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