Description
Congratulations! If you’re seeing this, then presumably you’ve managed to:
* Install Java
* Install Eclipse
* Install Git
* Created a GitHub account
* Accepted the A1 assignment link.
If you haven’t done one or more of those things, please do.
This repository should be a “private” repository and access to it is limited to yourself, KMP, and the COMP 401 LA team.
Now it’s time to create an Eclipse project based on this repository. While there is more than one way to do this, I find that
the easiest and most foolproof way is to follow the procedure demonstrated in this YouTube video:
https://www.youtube.com/watch?v=1v3ed8w1iEQ
Go ahead and watch the video and follow along. After you’re done you should have:
* Cloned this repository to your local machine.
* Created an Eclipse project connected to that repository.
The first thing we’ll do is make sure you’re able to run a program in Eclipse and provide input from the keyboard to that program. Follow this video and follow along:
https://youtu.be/NNI0I6ALfxU
Did it all work as expected? Is your Java version at least 10.0? If not, get yourself to office hours and/or see if there’s any helpful advice on Piazza for a similar issue or post a question on Piazza describing what seems to be going wrong. If all is well, let’s learn how to submit your assignments to Gradescope. Watch this video and follow along:
https://youtu.be/IpP38MSB1sM
Did you get your first point of the assignment? If yes, then congratulations. If not, better go work it out eventually, but you could also keep going with the assignment.
Now things are set up, here is the rest of the assignment.
### Scanner
This assignment requires you to make use of a Scanner object. You can read the documentation for Scanner here: https://docs.oracle.com/en/java/javase/12/docs/api/java.base/java/util/Scanner.html
A Scanner object is associated with a source of input. In our case, this will be keyboard input from the console. By default, a Scanner object will parse input as whitespace-separated tokens and provides methods for parsing the next available token as a particular type.
For example, the method next() will retrieve the next token (i.e., word) as a String. Similarly, the method nextInt() interprets and returns the value of the next token as an integer while nextDouble() will interpret the next token as a double value. For this assignment, you shouldn’t have to use any Scanner methods other than next(), nextInt(), and nextDouble(). In particular, you should avoid using nextLine(). Do not assume that the input is organized into lines. All of the input could be on a single line or each word might be on a different line or something in between. Do not make any assumptions about the input being organized into lines.
For this assignment, you can assume that the input will always be valid and conform to the description below. In other words, you do not have to worry about validating the input or being able to deal with unexpected input.
## A1Novice
This program will read in data that represents shopping orders from a number of customers and report the total amount spent on a per customer basis. The input provided will have the following form:
* The first input will be an integer indicating the total number of customers.
* Then, for each customer, the input will be comprised of:
* The first name of the customer
* The last name of the customer
* The number of items bought by the customer.
* For each item bought, the input will then contain:
* An integer quantity of the item bought
* The name of the item (you can assume these will be single words)
* The price of the item as a double
For each customer, your program should print one line of ouptut in the following form:
“`
F. LAST: TOTAL
“`
Where “`F.“` represents the first letter initial of the first name of the customer, LAST represents the last name of the customer, and TOTAL is the total cost of the items purchased to two decimal places.
For example, the following input:
“`
3
Carrie Brownstein 3
2 Banana 0.75
1 Orange 1.25
2 Milk 3.15
Corin Tucker 2
3 Banana 0.75
2 Sponge 1.15
Janet Weiss 1
5 Salami 2.50
“`
Should produce the following output:
“`
C. Brownstein: 9.05
C. Tucker: 4.55
J. Weiss: 12.50
“`
## A1Adept
This program will also read in shopping order data but now provided in a slightly different form and will produce output that reports the customers that were the biggest and smallets spenders as well as the average bill for all customers.
Input to the program will have the following form:
* An integer count of the number of items in the store.
* Then for each item in the store…
* The name of each item (a single word)
* The price of the item
* An integer count of the number of customers
* Then for each customer…
* The first name of the customer
* The last name of the customer
* An integer count of the number of items the customer bought.
* For each of the items bought…
* The quantity of the item bought
* The name of the item
The output of the program should be exactly three lines in the following form:
“`
Biggest: FIRST LAST (AMOUNT)
Smallest: FIRST LAST (AMOUNT)
Average: AVERAGE
“`
… where FIRST and LAST are the first and last names of the biggest and smallest spenders as appropriate, AMOUNT is the amount spent, and AVERAGE is the average amount spent. For example, the following input:
“`
6
Apple 0.25
Banana 0.75
Milk 3.15
Orange 1.25
Salami 2.50
Sponge 1.15
3
Carrie Brownstein 3 2 Banana 1 Orange 2 Milk
Corin Tucker 2 3 Banana 2 Sponge
Janet Weiss 1 5 Salami
“`
Should produce the following output:
“`
Biggest: Janet Weiss (12.50)
Smallest: Corin Tucker (4.55)
Average: 8.70
“`
## A1Jedi
This program will read in data with the same form as A1Adept and as output will report for each item how many different customers bought that item and the total quantity of the item bought by all customers. Each item should be reported in the same order as specified in the beginning of the input. Each report line should have the form:
“`
NUMBER customers bought TOTAL ITEM
“`
… where NUMBER is the number of customers that bought the item, TOTAL is the total quantity of the item bought by all customers and ITEM is the item name.
If no customers bought an item, then the report for that item should be in the form:
“`
No customers bought ITEM
“`
For example, the same input provided as an example for A1Adept above should produce the following output for A1Jedi:
“`
No customers bought Apple
2 customers bought 5 Banana
1 customers bought 2 Milk
1 customers bought 1 Orange
1 customers bought 5 Salami
1 customers bought 2 Sponge
“`
## Hints
In order to convert a double (let’s call it “value”) to a String with two decimal places, use the following expression:
“`
String.format(“%.2f, value)
“`
You can not assume that the same item may not show up more than once for the same customer. For example, the following is valid input for A1Adept or A1Jedi that will produce the same results as above.
“`
6
Apple 0.25
Banana 0.75
Milk 3.15
Orange 1.25
Salami 2.50
Sponge 1.15
3
Carrie Brownstein 5 1 Banana 1 Orange 1 Milk 1 Banana 1 Milk
Corin Tucker 3 1 Banana 2 Sponge 2 Banana
Janet Weiss 3 2 Salami 2 Salami 1 Salami
“`
You should also be sure to only use next, nextInt, and nextDouble as methods of the Scanner object in order to read the next expected input word as either a String, int, or double without trying to process the input as lines. You should not assume any sort of line structure to the input. In other words, the following is a valid equivalent to the example input provided above:
“`
6 Apple 0.25 Banana 0.75 Milk 3.15 Orange 1.25 Salami 2.50 Sponge 1.15 3 Carrie
Brownstein 5 1 Banana 1 Orange 1 Milk 1 Banana 1 Milk Corin Tucker 3 1 Banana 2
Sponge 2 Banana Janet Weiss 3 2 Salami 2 Salami 1 Salami
“`
