Java: An Introduction to Problem Solving and Programming (8th Edition)
8th Edition
ISBN: 9780134462035
Author: Walter Savitch
Publisher: PEARSON
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Question
Chapter 7, Problem 8PP
Program Plan Intro
Shoulder surfing
Program Plan:
- Import required package.
- Define “AuthenticateTest” class.
- Define main function.
- Initializes actual PIN.
- Create an array “randomDigits” for randomly generated digits.
- Create an array “userEnteredDigits” for digits entered by the user.
- Generate random numbers from “1” to “3” for each digit using for loop.
- Display the sequence of PIN and NUM to screen.
- Display “10” digits random numbers for “NUM”.
- Create object for scanner class.
- Display user prompt statement.
- Read the five digits PIN number from user.
- Extract the digits from the code and store in the “userEnteredDigits” array.
- Convert char to corresponding digit.
- Check whether the user entered password is equal to random PIN number of actual PIN numbers by calling the method “checkValidPassword()”.
- If it is match, then display the message “Your password matches correctly!”.
- Otherwise, display the message “Invalid password.”.
- Define the boolean method “checkValidPassword()” with three arguments
- Check PIN numbers one by one using “for” loop. If the user entered PIN is not equal to actual PIN, then returns “false”.
- Define main function.
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A high school has 1000 students and 1000 lockers, one locker for each student. On the
first day of school, the principal plays the following game: She asks the first student to open all the lockers. She then asks the second student to close all the even-numbered lockers. The third student is asked to check every third locker. If it is open, the student closes it; if it is closed, the student opens it. The fourth student is asked to check every fourth locker. If it is open, the student closes it; if it is closed, the student opens it. The remaining students continue this game. In general, the nth student checks every nth locker. If the locker is open, the student closes it; if it is closed, the student opens it. After all the students have taken their turns, some of the lockers are open and some are closed. Write a program that prompts the user to enter the number of lockers in a school. After the game is over, the program outputs the number of lockers and the…
Chapter 7 Solutions
Java: An Introduction to Problem Solving and Programming (8th Edition)
Ch. 7.1 - What output will be produced by the following...Ch. 7.1 - What output will be produced by the following...Ch. 7.1 - What output will be produced by the following...Ch. 7.1 - Consider the following array: int [] a = new...Ch. 7.1 - What is wrong with the following code to...Ch. 7.1 - Write a complete Java program that reads 20 values...Ch. 7.2 - Write some Java code that will declare an array...Ch. 7.2 - Rewrite the method displayResults of the program...Ch. 7.2 - What output will be produced by the following...Ch. 7.2 - Give the definition of a static method called...
Ch. 7.2 - Give the definition of a static method called...Ch. 7.2 - Prob. 12STQCh. 7.2 - The following method compiles and executes but...Ch. 7.2 - Suppose that we add the following method to the...Ch. 7.3 - Prob. 15STQCh. 7.3 - Replace the last loop in Listing 7.8 with a loop...Ch. 7.3 - Suppose a is an array of values of type double....Ch. 7.3 - Suppose a is an array of values of type double...Ch. 7.3 - Prob. 19STQCh. 7.3 - Consider the partially filled array a from...Ch. 7.3 - Repeat the previous question, but this time assume...Ch. 7.3 - Write an accessor method getEntryArray for the...Ch. 7.4 - Prob. 23STQCh. 7.4 - Write the invocation of the method selectionSort...Ch. 7.4 - How would you need to change the method...Ch. 7.4 - How would you need to change the method...Ch. 7.4 - Consider an array b of int values in which a value...Ch. 7.5 - What output is produced by the following code?...Ch. 7.5 - Revise the method showTable in Listing 7.13 so...Ch. 7.5 - Write code that will fill the following array a...Ch. 7.5 - Write a void method called display such that the...Ch. 7.6 - Prob. 33STQCh. 7.6 - Prob. 34STQCh. 7 - Write a program in a class NumberAboveAverage that...Ch. 7 - Write a program in a class CountFamiles that...Ch. 7 - Write a program in a class CountPoor that counts...Ch. 7 - Write a program in a class FlowerCounter that...Ch. 7 - Write a program in a class characterFrequency that...Ch. 7 - Create a class Ledger that will record the sales...Ch. 7 - Define the following methods for the class Ledger,...Ch. 7 - Write a static method isStrictlyIncreasing (double...Ch. 7 - Write a static method removeDuplicates(Character[]...Ch. 7 - Write a static method remove {int v, int [] in}...Ch. 7 - Suppose that we are selling boxes of candy for a...Ch. 7 - Create a class polynomial that is used to evaluate...Ch. 7 - Write a method beyond LastEntry (position) for the...Ch. 7 - Revise the class OneWayNoRepeatsList, as given in...Ch. 7 - Write a static method for selection sort that will...Ch. 7 - Overload the method selectionSort in Listing 7.10...Ch. 7 - Revise the method selectionSort that appears in...Ch. 7 - Prob. 18ECh. 7 - Write a sequential search of an array of integers,...Ch. 7 - Write a static method findFigure (picture,...Ch. 7 - Write a static method blur (double [] [] picture)...Ch. 7 - Write a program that reads integers, one per line,...Ch. 7 - The following code creates a small phone book. An...Ch. 7 - Write the method rotateRight that takes an array...Ch. 7 - The following code creates a ragged 2D array. The...Ch. 7 - Write a program that will read a line of text that...Ch. 7 - A palindrome is a word or phrase that reads the...Ch. 7 - Add a method bubbleSort to the class ArraySorter,...Ch. 7 - Add a method insertionSort to the class...Ch. 7 - The class TimeBook in Listing 7.14 is not really...Ch. 7 - Define a class called TicTacToe. An object of type...Ch. 7 - Repeat Programming Project 10 from Chapter 5 but...Ch. 7 - Prob. 8PPCh. 7 - Write a GUI application that displays a picture of...Ch. 7 - ELIZA was a program written in 1966 that parodied...Ch. 7 - Prob. 11PPCh. 7 - Create a GUI application that draws the following...Ch. 7 - Practice Program 2 used two arrays to implement a...Ch. 7 - Practice Program 5.4 asked you to define Trivia...
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