# Say

Given a number from 0 to 999,999,999,999, spell out that number in English.

## Step 1

Handle the basic case of 0 through 99.

If the input to the program is `22`, then the output should be
`'twenty-two'`.

Your program should complain loudly if given a number outside the
blessed range.

Some good test cases for this program are:

- 0
- 14
- 50
- 98
- -1
- 100

### Extension

If you're on a Mac, shell out to Mac OS X's `say` program to talk out
loud.

## Step 2

Implement breaking a number up into chunks of thousands.

So `1234567890` should yield a list like 1, 234, 567, and 890, while the
far simpler `1000` should yield just 1 and 0.

The program must also report any values that are out of range.

## Step 3

Now handle inserting the appropriate scale word between those chunks.

So `1234567890` should yield `'1 billion 234 million 567 thousand 890'`

The program must also report any values that are out of range.  It's
fine to stop at "trillion".

## Step 4

Put it all together to get nothing but plain English.

`12345` should give `twelve thousand three hundred forty-five`.

The program must also report any values that are out of range.

### Extensions

Use _and_ (correctly) when spelling out the number in English:

- 14 becomes "fourteen".
- 100 becomes "one hundred".
- 120 becomes "one hundred and twenty".
- 1002 becomes "one thousand and two".
- 1323 becomes "one thousand three hundred and twenty-three".

## Getting Started

Make sure you have read the
[C page](http://exercism.io/languages/c) on the Exercism site. This covers
the basic information on setting up the development environment expected
by the exercises.


## Passing the Tests

Get the first test compiling, linking and passing by following the [three
rules of test-driven development][3-tdd-rules].

The included makefile can be used to create and run the tests using the `test`
task.

    make test

Create just the functions you need to satisfy any compiler errors and get the
test to fail. Then write just enough code to get the test to pass. Once you've
done that, move onto the next test.

[3-tdd-rules]: http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd

As you progress through the tests, take the time to refactor your
implementation for readability and expressiveness and then go on to the next
test.

Try to use standard C99 facilities in preference to writing your own
low-level algorithms or facilities by hand.

## Source

A variation on JavaRanch CattleDrive, exercise 4a [http://www.javaranch.com/say.jsp](http://www.javaranch.com/say.jsp)

## Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.