Mastering Physics Online Test
Go to Masteringphysics.com, and solve the questions posted on sunday. There is time limit 90minutes.
Once you start, don’t open any other assignment until you complete this one.
(Otherwise you’ll lose any time remaining for this assignment.)
If you leave this assignment for any reason, the timer will not stop counting down.
To get credit for an item in the assignment, you must complete ALL of its parts (A, B, etc.).
COMP248/Winter 2017 – Assignment 3 Page 1 of 7
Concordia University
COMP 248 – Winter 2017
Assignment 3
Due Date: By 11:59pm Wednesday March 22, 2017
Evaluation: 4% of final mark (see marking rubric at the end of this handout)
Late Submission: none accepted
Purpose: The purpose of this assignment is to help you learn Java flow of
control statements (nested loops), arrays of primitive types, 2-
dimensional arrays and classes.
CEAB/CIPS Attributes: Design/Problem analysis/Communication Skills
General Guidelines When Writing Programs:
Please refer to the handout of Assignment #1.
Question 1 – One dimensional array & while loops
There are 30 hockey teams in the NHL (National Hockey League). Some stores
have vending machines that dispense miniature team hockey pucks for a toonie
($2) each. When you put in a toonie you never know which puck you will get;
any one of the 30 team pucks is as likely as any other to be dispensed by the
machine. They are given out at random.
For this exercise we will limit the teams to 10.
Your job is to write a program to simulate the dispensing of NHL miniature pucks until one of
each 10 miniature team hockey pucks is dispensed.
Your program should proceed as follows:
1. Display a welcome message and ask the user to enter their name.
2. Store your 10 favorite hockey teams’ name in an array of String. Assign the team names in
the declaration statement directly.
3. Your program should loop(use a while loop) until at least one miniature puck of each team
has been dispensed. Create an integer array of size 10, which will serve as a counter array to
keep track of the number of each team puck dispensed by the vending machine. You will
need to use the Math.random()function to randomly dispense a miniature puck. The
Math.random() method returns a double value with a positive sign, greater than or
equal to 0.0 and less than 1.0.
4. Once you have accumulated at least one of each puck, display how many of each team puck
you had to purchase, the total number of pucks purchased and the total cost in a
personalized message.
Note:
1. Store the number of teams and the cost of a miniature puck as constants.
2. Feel free to change the messages and prompt. You can pick any 10 hockey teams you like.
3. Figure 1 is a sample output screen which illustrates the expected behavior of your program.
http://www.terapeak.com/worth/montre
al-canadiens-souvenir-official-pucktrench-nhl-hockey-puck/121895949004/
COMP248/Winter 2017 – Assignment 3 Page 2 of 7
4. User input is marked by
Question 2 – 2-dimensional arrays, while loops & do/while loops
Write a Java program which fill a 2D-array square array as per a given patterns 1 and 2 (figure 2)
and display them.
Your program should proceed as follows:
1. Display a welcome message.
2. Prompt the user for an integer which is ?3. If the number entered is < 3, keep prompting
the user until they enter a number ?3 (use a do/while). This number will determine the
size of the square array.
3. Fill the array as per pattern 1 and display it using printf to format the array.
4. Fill the same array as per pattern 2 and display it using printf to format the array.
5. Display a closing message.
= 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 =
= 0 0 =
= 0 NHL Miniature Hockey Puck Vending Machine 0 =
= 0 0 =
= 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 = 0 =
Hello, what is your first name? Nancy
Welcome Nancy! Let’s see how much money you will need to spend to
get all of the pucks.
Here is the breakdown of the pucks dispensed:
Montreal Canadians: 2
Boston Bruins: 4
Chicago BlackHawks: 2
Detroit Red Wings: 3
New York Rangers: 3
Buffalo Sabres: 1
Philadelphia Flyers: 1
Winnipeg Jets: 4
Vancouver Canucks: 5
Ottawa Senators: 8
Wow Nancy, you bought a total of 33 pucks at a total cost of $66 to
get a miniature puck of each team.
Enjoy them!
Figure 1- Sample output for Question 1
COMP248/Winter 2017 – Assignment 3 Page 3 of 7
Figures 3 and 4 are screen captures to illustrate the expected behavior of your program.
Pattern 1 Pattern 2 (Some slots are shaded to
help you see the pattern.
Figure 2- Illustrations of patterns
Figure 3- Sample output #1 for Question 2
COMP248/Winter 2017 – Assignment 3 Page 4 of 7
Note:
– You can use static methods if you like.
– User input is marked with
Question 3 – Defining a class
“Combination locks found on padlocks, lockers, or safes may use a single dial
which interacts with several parallel discs or cams. Customarily, a lock of this
type is opened by rotating the dial clockwise to the first numeral, counter
clockwise to the second, and so on in an alternating fashion until the last
numeral is reached. The cams typically have an indentation or notch, and
when the correct combination is entered, the notches align, allowing the latch
to fit into them and open the lock. “
(https://en.wikipedia.org/wiki/Combination_lock#Single-dial_locks)
a) Create a class named CombinationLock that stores information about a 3-number dialing
combination lock. It contain the following:
? Four private instance variables that store the 3 combination numbers required to open
the lock and a Boolean variable that will indicate whether the lock is open or closed (true
if open, false if closed).
? 2 constructors:
http://shopimg.com/products/c
ombination-lock
Figure 4- Sample output #2 for Question 2
COMP248/Winter 2017 – Assignment 3 Page 5 of 7
– default constructor – sets the 3 combination numbers to zero and marks the lock as
closed.
– three parameter constructor – sets the 3 combination numbers to the three passed
integers and marks the lock as open.
? No accessor methods
? A Boolean mutator method called setCombination, which is a 3 parameter method
and sets the 3 combination numbers to the 3 passed numbers. It can only change the
combination if the lock is closed. If the lock is open it returns false as it could not
change the combination. If the lock is closed it returns true after it has reset the
combination.
? A public void method called closeLock() which set the status of the lock as closed.
? A public Boolean method isLockOpen() which returns true if the lock is open and
false if it is closed.
? A public Boolean method called openLock() which is a 3 parameter method whose
purpose is to checks if the supplied combination is the correct one. If it is correct it sets
the status to open and returns true. If it is incorrect it returns false.
? A public integer method HowManyCorrect() which is a 3 parameter method. It
returns the count of correct numbers in the supplied combination.
? A toString() method to return the combination of the lock in the following format:
Clockwise num1 – Counter-Clockwise num2 – Clockwise num3
where num1, num2 and num3 are the values of the instance variables corresponding to
the combination which will open the lock.
? An equals() method to test for equality of the combination of two objects of class
CombinationLock. We don’t care whether they are open or closed.
b) Write a driver to test your class from a) as follows:
i. Display a welcome message/banner.
ii. Declare 2 CombinationLock objects each using a different constructors (you decide
on the info) and output the description of the 2 object created. Methods to use:
constructors, toString()
iii. Open one of the locks: Try once with the incorrect combination, then try a second time
with the correct combination. In both cases display a status message as to the success
or failure to open the lock. Methods to use: openLock()
iv. Change the combination of one of the locks: Test your mutator method by changing
the combination of the lock you opened in the previous step. (Make sure both locks do
not have the same combination.) Remember you can only change the combination if
COMP248/Winter 2017 – Assignment 3 Page 6 of 7
the lock is closed. Methods to use: setCombination(),isLockOpen (),
closeLock()
v. Open the other lock: Try once with the incorrect combination and report back how
many of the entered numbers are correct. Try again with the correct combination and
display a congratulations message. Methods to use: openLock(),
howManyCorrect()
vi. Check 2 locks for equality: Test both locks for equality. Report the result and the
open/close status of each lock. Change the combinations of one of the locks to be the
same as the other. Test both locks for equality again and report the result as well as the
open/close status of each lock. . Methods to use: equals(), isLockOpen (),
setCombination().
vii. Closing message: Finish off with a closing message.
Following is a sample run to illustrate the expected behavior of your driver.
|—————————|
| Locksmith Program |
|—————————|
Combination for lock 1 is: Clockwise 0 – Counter-Clockwise 0 – Clockwise 0
Combination for lock 2 is: Clockwise 13 – Counter-Clockwise 7 – Clockwise 11
==> Attempting to open lock 1
Sorry the combination you supplied for lock 1 is incorrect
Congratulations you opened lock 1
===> Attempting to change the combination of lock 1
You can’t change the combination if the lock is open. Close the lock and try
again
Congratulations you successfully changed the combination of lock 1 to
Clockwise 3 – Counter-Clockwise 7 – Clockwise 11
===> Attempting to open lock 2
2 of the numbers are correct. Try again.
Congratulations you opened lock 2
===> Testing the two locks for equality
Lock 1 combination is: Clockwise 3 – Counter-Clockwise 7 – Clockwise 11
Lock 2 combination is: Clockwise 13 – Counter-Clockwise 7 – Clockwise 11
Combination of both locks is the NOT same
Lock 1 is not open
Lock 2 is open
Lock 1 combination is: Clockwise 3 – Counter-Clockwise 7 – Clockwise 11
Lock 2 combination is: Clockwise 13 – Counter-Clockwise 7 – Clockwise 11
Combination of both locks is the same
Lock 1 is not open
Lock 2 is open
Hope you are comfortable with the manipulation of objects after this!!!
COMP248/Winter 2017 – Assignment 3 Page 7 of 7
Submitting Assignment 3
– Zip the source code (the .java file only please) of this assignment.
– Naming convention for zip file: Create one zip file, containing the source files for your
assignment using the following naming convention:
? If the assignment is done by 1 student:
The zip file should be called a#_studentID, where # is the number of the assignment
and studentID is your student ID number.
For example, for this assignment, student 123456 would submit a zip file named
a3_123456.zip
? If the assignment is done by 2 students:
The zip file should be called a#_studentID1_studentID2, where # is the number of
the assignment studentID1 and studentID2 are your student ID numbers. For
example, for this assignment, student 123456 and 9876543 would submit a zip file
named a3_123456_9876543.zip
– For submission instructions please refer to the course web page.
– Assignments not submitted to the correct location or not in the requested format will not be
graded.
Evaluation Criteria for Assignment 3 (20 points)
Source Code
Programming Style (3 pts.)
Comments-description of variables and constants-description of
the program (authors, date, purpose) 0.5 pts.
Clear prompts to user & clear message with output 1 pt.
Use of significant names for identifiers 0.5 pts.
Indentation and readability 0.5 pts.
Welcome Banner/Closing message 0.5 pts.
Question 1 (5 pts.)
Set up array of team names 1 pt.
Loop until have at least one of each puck; keep counters 3 pts.
Display number of each puck, total puck & cost 1 pt.
Question 2 (6 pts.)
Validating user input 1 pt.
Fill array with pattern 1 2 pts.
Fill array with pattern 2 2 pts.
Display array properly formatted 1 pt.
Question 3 (6 pts.)
Declare instance variables 0.5 pts.
Constructors – Mutator 1.5 pts.
closeLock() – isOpen() – openLock() 1.5 pts.
howManyCorrect() 0.5 pts.
toString() – equals() 0.5 pts.
Driver 1.5 pts.
TOTAL 20 pts.
