Computing Essentials 2019 27th Edition
19th Edition
ISBN: 9781260096057
Author: By Timothy O'Leary and Linda O'Leary and Daniel O'Leary
Publisher: McGraw-Hill Education
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Chapter 12, Problem 4OE
Program Plan Intro
System maintenance and the time it occurs.
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Consider the following sequential circuit:
CLOCK
a. Define the diagram circuit variables (5 pts)
b. Derive the Flip-Flop input equations) (5 pts)
c. Derive the circuit output equation (5 pts)
d. Derive the state table of the circuit (5 pts)
e. Derive the state diagram for this circuit (5 pts)
Clk
A
D
B
B'
CIK
Question 2 (25 pts)
A sequential circuit with two D flip-flops A and B, two inputs x and y, and one output z is
specified by the following next-state and output equations:
A(t + 1) = xy' + xB
B(t + 1) = xA + xB'
z = A
a. Draw the logic diagram of the circuit. (5 pts)
b. List the state table for the sequential circuit. (10 pts)
c. Draw the corresponding state diagram. (10 pts)
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.
Chapter 12 Solutions
Computing Essentials 2019 27th Edition
Ch. 12 - Prob. 1CCCh. 12 - Prob. 2CCCh. 12 - Prob. 3CCCh. 12 - Prob. 4CCCh. 12 - Prob. 5CCCh. 12 - Prob. 6CCCh. 12 - Prob. 7CCCh. 12 - Prob. 8CCCh. 12 - Prob. 9CCCh. 12 - Prob. 10CC
Ch. 12 - Prob. 11CCCh. 12 - Prob. 12CCCh. 12 - Prob. 13CCCh. 12 - Prob. 14CCCh. 12 - Prob. 15CCCh. 12 - Prob. 16CCCh. 12 - Prob. 17CCCh. 12 - Prob. 18CCCh. 12 - Prob. 19CCCh. 12 - Prob. 20CCCh. 12 - Prob. 21CCCh. 12 - Prob. 22CCCh. 12 - Prob. 1MCCh. 12 - Prob. 2MCCh. 12 - Prob. 3MCCh. 12 - Prob. 4MCCh. 12 - Prob. 5MCCh. 12 - Prob. 6MCCh. 12 - Prob. 7MCCh. 12 - Prob. 8MCCh. 12 - Prob. 9MCCh. 12 - Prob. 10MCCh. 12 - Prob. 1MCh. 12 - Prob. 1OECh. 12 - Prob. 2OECh. 12 - Prob. 3OECh. 12 - Prob. 4OECh. 12 - Prob. 5OECh. 12 - Prob. 1DCh. 12 - Prob. 2D
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