2 Countdown

“Countdown” is an English gameshow. In one of the Countdown games, contestants are given a set of random letters

which the contestants unscramble to ﬁnd the longest word that can they can make using a subset from the randomly

chosen letters. The more entertaining variant of this show is called “8 Out of 10 Cats Does Countdown” where come-

dians perform the same tasks.

For example, given the set of letters “ionsomsti”, we can form the following words: “in”, “insist”, “mission”, “mito-

sis”, “omission”. Out of these words, the longest word is ”omission”, so “omission” would be the winning word from

the set of letters.

On “Countdown”, the number of scrambled letters provided is 9 and therefore the longest words possible can contain

9 letters. For our solution, we will not bound the maximum number of characters in the set of letters. We will instead

pass a string of letters and the string will dictate the maximum length of the available letters to choose from.

2.1 Instructions

This problem is similar to trying to ﬁnd all anagrams in a dictionary for a given word or determining if a sentance is

a pangram; however, it is slightly more challenging because there is no guarantee that it is possible to use all letters

provided in the scrambled set of letters.

We will use the WordTool and dictionary of words to try to ﬁnd the longest word possible to form from the scramble.

I have edited the words ﬁle to remove entries from the dictionary that contain special characters like contractions and

abbreviations, so you should use the words ﬁle provided in the assignment ﬁle.

A framework for this program has been provided in Countdown.java. You will implement three methods in the

Countdown class:

• WordGame

• contains

• Test3

You will not alter any of the other code in the framework, you will use the provided interfaces for the above methods,

and there is no need to add additional methods. There are three places that are marked with TODO that you will focus

on.

Read the documentation associated with each method and fulﬁll the requirements outlined by that method’s documen-

tation. WordGame is intended to handle the selection of a word from the dictionary and then using the contains

method to see if the word contains a subset of the letters provided. The contains method is intended to see if the

word is contained in the set of letters.

The framework provides a set of “Unit Tests” to evaluate the algorithm. The ﬁrst two unit tests are provided in the

methods Test1 and Test2. You will implement your own unit test in Test3. Your unit test must include a set of

letters containing at least 9 unique letters and must contain at least 3 vowels. Your program must pass all three tests to

be considered fully correct.

There may be a number of words with the same length that can be formed using the set of letters. We do not necessarily

need to know all words that can be formed using the set of letters, so we will pick the ﬁrst word in the alphabet that is

the longest word. This offers a slight optimization but mostly it ensures that everyone gets the same answer to the ﬁrst

two unit tests.