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# Prime Factors

Compute the prime factors of a given natural number.

A prime number is only evenly divisible by itself and 1.

Note that 1 is not a prime number.

## Example

What are the prime factors of 60?

- Our first divisor is 2. 2 goes into 60, leaving 30.
- 2 goes into 30, leaving 15.
  - 2 doesn't go cleanly into 15. So let's move on to our next divisor, 3.
- 3 goes cleanly into 15, leaving 5.
  - 3 does not go cleanly into 5. The next possible factor is 4.
  - 4 does not go cleanly into 5. The next possible factor is 5.
- 5 does go cleanly into 5.
- We're left only with 1, so now, we're done.

Our successful divisors in that computation represent the list of prime
factors of 60: 2, 2, 3, and 5.

You can check this yourself:

- 2 * 2 * 3 * 5
- = 4 * 15
- = 60
- Success!

## Loading your exercise implementation in PolyML

```
$ poly --use {exercise}.sml
```

Or:

```
$ poly
> use "{exercise}.sml";
```

**Note:** You have to replace {exercise}.

## Running the tests

```
$ poly -q --use test.sml
```

## Feedback, Issues, Pull Requests

The [exercism/sml](https://github.com/exercism/sml) repository on
GitHub is the home for all of the Standard ML exercises.

If you have feedback about an exercise, or want to help implementing a new
one, head over there and create an issue. We'll do our best to help you!

## Source

The Prime Factors Kata by Uncle Bob [http://butunclebob.com/ArticleS.UncleBob.ThePrimeFactorsKata](http://butunclebob.com/ArticleS.UncleBob.ThePrimeFactorsKata)

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

Version data entries

159 entries across 159 versions & 1 rubygems

Version Path
trackler-2.2.1.180 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.179 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.178 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.177 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.176 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.175 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.174 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.173 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.172 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.171 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.170 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.169 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.167 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.166 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.165 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.164 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.163 tracks/sml/exercises/prime-factors/README.md
trackler-2.2.1.162 tracks/sml/exercises/prime-factors/README.md
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trackler-2.2.1.160 tracks/sml/exercises/prime-factors/README.md