Introduction To Algorithms, Third Edition (international Edition)
3rd Edition
ISBN: 9780262533058
Author: Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, Clifford Stein
Publisher: TRILITERAL
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Chapter 32.4, Problem 8E
Program Plan Intro
To prove that
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5. Word FrequencyWrite a program that reads the contents of a text file. The program should create a dictio-nary in which the keys are the individual words found in the file and the values are the number of times each word appears. For example, if the word “the” appears 128 times, the dictionary would contain an element with 'the' as the key and 128 as the value. The program should either display the frequency of each word or create a second file containing a list of each word and its frequency.
3.) File Encryption and DecryptionWrite a program that uses a dictionary to assign “codes” to each letter of the alphabet. For example:
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.
Returns an US standard formatted phone number, in the format of
(xxx) xxx-xxxx
the AreaCode, Prefix and number being each part in order.
Testing Hint: We be exact on the format of the number when
testing this method. Make sure you think about how to convert
33 to 033 or numbers like that when setting your string format. Reminder
the %02d - requires the length to be 2, with 0 padding at the front if a single
digit number is passed in.
Chapter 32 Solutions
Introduction To Algorithms, Third Edition (international Edition)
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