CSC241 Array of Circular Queues

In a single-file project called Cashiers.java, code a user-defined class called Cashiers that consists of:

• A 3 x 6 integer matrix to store numbers of up to 6 customers in the lines (queues) of 3 cashiers
• Two arrays, front and back, each of size 3, to follow a circular queue protocol
• An array, currentSize, of size 3, to keep track of the size of each line
• A single variable customer, initially 1, which increments every time a new customer joins a queue.

The following methods need to be coded for this class:

• A constructor Cashiers()
• clear()
• fill()
• display()
• int dequeue(int which), where which is the queue number 0, 1, or 2
• boolean enqueue(), which picks the shortest queue (if a tie, the lowest number)

Use the Cashiers class also to contain a main method that repeatedly asks the user:

Input command E or 1 or 2 or 3 or F or C or Q

Permit lower case by converting to upper case. Validate with the message

Invalid input!

if the user does not input one of these 7 options. Here are the actions that need to be coded, using one object of the user-defined class Cashiers:

• E = enqueuer, using the shortest queue (if a tie, use the lowest-numbered queue)
• 1, 2, or 3 = dequeuer from queue 0, 1, or 2.
• F = clear all queues and then fill up again
• C = clear all queues
• Q = quit

After each input, display the data structure again. Here is a sample display:

0 4F 7 10B 0 0
0 0 8F 11B 0 0
3F 6 9 12B 0 0

For each entry, give the customer number (0) if location not used, and list F or B or FB after the number as appropriate, where F labels the front and B the back of the queue.