Free response #3

Quilt.txt

One thing Stanford students get too much of is free T-shirts. There's 
free T-shirts from career fairs, from your academic department, from 
dorm events, from campus events, from student groups, etc. etc. etc. 
So one thing we like to do with our old T-shirts is make quilts out of 
them!

Imagine we had 9 T-shirts. We could stitch them together a 3x3 quilt, 
where each square unit is a T-shirt. So something like:

__________________________________
|          |          |          |
|  Tshirt  |  Tshirt  |  Tshirt  |
|          |          |          |
|__________|__________|__________|
|          |          |          |
|  Tshirt  |  Tshirt  |  Tshirt  |
|          |          |          |
|__________|__________|__________|
|          |          |          |
|  Tshirt  |  Tshirt  |  Tshirt  |
|          |          |          |
|__________|__________|__________|

Okay...so let's turn this into a programming question. Each T-shirt is 
going to be a String (where the String is the T-shirt text). I want 
you to write a class QuiltMaker that takes a bunch of T-shirts (i.e. a 
bunch of Strings) and returns a 2D array that represents how they 
would be arranged in a quilt.

So I need to be able to do the following:
QuiltMaker qm = new QuiltMaker();
qm.addShirt("Quicksilver");
qm.addShirt("Class of 2011");
qm.addShirt("Symphony Orchestra '15");
....
boolean canMakeQuilt = qm.canMakeQuilt();
....
String[][] layout = qm.getQuilt();

Write all the necessary things to make the above code compile. Besides 
whatever class stuff and plumbing you need to setup, there are two 
methods you need to write: "canMakeQuilt" and "getQuilt".

"canMakeQuilt" returns whether or not the QuiltMaker currently has 
enough T-shirts to make a quilt. A quilt must always be 3 T-shirts 
wide and have at least three rows (this means you need at least nine 
T-shirts to make a quilt). Furthermore the quilt needs to be 
rectangular so you can't make something jagged like:

__________________________________
|          |          |          |
|  Tshirt  |  Tshirt  |  Tshirt  |
|          |          |          |
|__________|__________|__________|
|          |          |          |
|  Tshirt  |  Tshirt  |  Tshirt  |
|          |          |          |
|__________|__________|__________|
|          |          |          |
|  Tshirt  |  Tshirt  |  Tshirt  |
|          |          |          |
|__________|__________|__________|
|          |          |
|  Tshirt  |  Tshirt  |
|          |          |
|__________|__________|

This means that you can't make a quilt with 10 or 11 T-shirts. More 
generally, you can only make a quilt when the number of T-shirts you 
have is greater than 9 and divisible by 3 (do you see how this follows 
from the rules above?).

"getQuilt" returns a 2D array of the T-shirt layout (which means a 2D 
array of Strings). The shirts can be arranged in any way you like. 
If it's not possible to make a quilt (i.e. you don't have the right 
number of shirts), then just return null.

Here you go https://gist.github.com/DukeOfXor/bbc13b3243839f0e7de3576549fc6655