Starting Out with Python Plus MyLab Programming with Pearson eText -- Access Card Package (4th Edition)
4th Edition
ISBN: 9780134543666
Author: Tony Gaddis
Publisher: PEARSON
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Textbook Question
Chapter 9, Problem 3PE
File Encryption and Decryption
Write a
codes = { 'A' :, '%', 'a' : '9', 'B' : '@', 'b' : '#', etc . . .}
Using this example, the letter A would be assigned the symbol %, the letter a would be assigned the number 9, the letter B would be assigned the symbol @, and so forth. The program should open a specified text file, read its contents, then use the dictionary to write an encrypted version of the file’s contents to a second file. Each character in the second file should contain the code for the corresponding character in the first file.
Write a second program that opens an encrypted file and displays its decrypted contents on the screen.
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Word IndexWrite a python program that reads the contents of a text file. The program should create a dictionary inwhich the key-value pairs are described as follows:Key. The keys are the individual words found in the file.576Values. Each value is a list that contains the line numbers in the file where the word (thekey) is found.For example, suppose the word “robot” is found in lines 7, 18, 94, and 138. The dictionarywould contain an element in which the key was the string “robot”, and the value was a listcontaining the numbers 7, 18, 94, and 138.Once the dictionary is built, the program should create another text file, known as a word index,listing the contents of the dictionary. The word index file should contain an alphabetical listingof the words that are stored as keys in the dictionary, along with the line numbers where thewords appear in the original file. Figure 9-1 shows an example of an original text file(Kennedy.txt) and its index file (index.txt
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7.9 LAB: Sorting TV Shows (dictionaries and lists)
Write a program that first reads in the name of an input file and then reads the input file using the file.readlines() method. The input file contains an unsorted list of number of seasons followed by the corresponding TV show. Your program should put the contents of the input file into a dictionary where the number of seasons are the keys, and a list of TV shows are the values (since multiple shows could have the same number of seasons).
Sort the dictionary by key (least to greatest) and output the results to a file named output_keys.txt, separating multiple TV shows associated with the same key with a semicolon (;). Next, sort the dictionary by values (alphabetical order), and output the results to a file named output_titles.txt.
Ex: If the input is:
file1.txt
and the contents of file1.txt are:
20
Gunsmoke
30
The Simpsons
10
Will & Grace
14
Dallas
20
Law & Order
12
Murder, She Wrote
the file…
Chapter 9 Solutions
Starting Out with Python Plus MyLab Programming with Pearson eText -- Access Card Package (4th Edition)
Ch. 9.1 - An element in a dictionary has two parts. What are...Ch. 9.1 - Which part of a dictionary element must be...Ch. 9.1 - Suppose ' start' : 1472 is an element in a...Ch. 9.1 - Suppose a dictionary named employee has been...Ch. 9.1 - What will the following code display? stuff = {1 :...Ch. 9.1 - Prob. 6CPCh. 9.1 - Suppose a dictionary named inventory exists. What...Ch. 9.1 - What will the following code display? stuff = {1 :...Ch. 9.1 - What will the following code display? stuff = {1 :...Ch. 9.1 - What is the difference between the dictionary...
Ch. 9.1 - Prob. 11CPCh. 9.1 - Prob. 12CPCh. 9.1 - What does the values method return?Ch. 9.2 - Prob. 14CPCh. 9.2 - Prob. 15CPCh. 9.2 - Prob. 16CPCh. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - Prob. 22CPCh. 9.2 - After the following statement executes, what...Ch. 9.2 - After the following statement executes, what...Ch. 9.2 - Prob. 25CPCh. 9.2 - Prob. 26CPCh. 9.2 - After the following code executes, what elements...Ch. 9.2 - Prob. 28CPCh. 9.2 - After the following code executes, what elements...Ch. 9.2 - After the following code executes, what elements...Ch. 9.2 - After the following code executes, what elements...Ch. 9.2 - Prob. 32CPCh. 9.3 - Prob. 33CPCh. 9.3 - When you open a file for the purpose of saving a...Ch. 9.3 - When you open a file for the purpose of retrieving...Ch. 9.3 - Prob. 36CPCh. 9.3 - Prob. 37CPCh. 9.3 - Prob. 38CPCh. 9 - You can use the __________ operator to determine...Ch. 9 - You use ________ to delete an element from a...Ch. 9 - The ________ function returns the number of...Ch. 9 - You can use_________ to create an empty...Ch. 9 - The _______ method returns a randomly selected...Ch. 9 - The __________ method returns the value associated...Ch. 9 - The __________ dictionary method returns the value...Ch. 9 - The ________ method returns all of a dictionary's...Ch. 9 - The following function returns the number of...Ch. 9 - Prob. 10MCCh. 9 - Prob. 11MCCh. 9 - This set method removes an element, but does not...Ch. 9 - Prob. 13MCCh. 9 - Prob. 14MCCh. 9 - This operator can be used to find the difference...Ch. 9 - Prob. 16MCCh. 9 - Prob. 17MCCh. 9 - The keys in a dictionary must be mutable objects.Ch. 9 - Dictionaries are not sequences.Ch. 9 - Prob. 3TFCh. 9 - Prob. 4TFCh. 9 - The dictionary method popitem does not raise an...Ch. 9 - The following statement creates an empty...Ch. 9 - Prob. 7TFCh. 9 - Prob. 8TFCh. 9 - Prob. 9TFCh. 9 - Prob. 10TFCh. 9 - What will the following code display? dct =...Ch. 9 - What will the following code display? dct =...Ch. 9 - What will the following code display? dct =...Ch. 9 - What will the following code display? stuff =...Ch. 9 - How do you delete an element from a dictionary?Ch. 9 - How do you determine the number of elements that...Ch. 9 - Prob. 7SACh. 9 - What values will the following code display? (Dont...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - After the following statement executes, what...Ch. 9 - What will the following code display? myset =...Ch. 9 - After the following code executes, what elements...Ch. 9 - Prob. 16SACh. 9 - Prob. 17SACh. 9 - Prob. 18SACh. 9 - After the following code executes, what elements...Ch. 9 - Prob. 20SACh. 9 - Write a statement that creates a dictionary...Ch. 9 - Write a statement that creates an empty...Ch. 9 - Assume the variable dct references a dictionary....Ch. 9 - Assume the variable dct references a dictionary....Ch. 9 - Prob. 5AWCh. 9 - Prob. 6AWCh. 9 - Prob. 7AWCh. 9 - Prob. 8AWCh. 9 - Prob. 9AWCh. 9 - Prob. 10AWCh. 9 - Assume the variable dct references a dictionary....Ch. 9 - Write code that retrieves and unpickles the...Ch. 9 - Course information Write a program that creates a...Ch. 9 - Capital Quiz The Capital Quiz Problem Write a...Ch. 9 - File Encryption and Decryption Write a program...Ch. 9 - Unique Words Write a program that opens a...Ch. 9 - Prob. 5PECh. 9 - File Analysis Write a program that reads the...Ch. 9 - World Series Winners In this chapters source code...Ch. 9 - Name and Email Addresses Write a program that...Ch. 9 - Blackjack Simulation Previously in this chapter...Ch. 9 - Word Index Write a program that reads the contents...
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