Perfect Numbers in Rust
Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60  120 CE) classification scheme for natural numbers.
1  exercism fetch rust perfectnumbers

Perfect Numbers
Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60  120 CE) classification scheme for natural numbers.
The Greek mathematician Nicomachus devised a classification scheme for natural numbers, identifying each as belonging uniquely to the categories of perfect, abundant, or deficient based on their aliquot sum. The aliquot sum is defined as the sum of the factors of a number not including the number itself. For example, the aliquot sum of 15 is (1 + 3 + 5) = 9

Perfect: aliquot sum = number
 6 is a perfect number because (1 + 2 + 3) = 6
 28 is a perfect number because (1 + 2 + 4 + 7 + 14) = 28

Abundant: aliquot sum > number
 12 is an abundant number because (1 + 2 + 3 + 4 + 6) = 16
 24 is an abundant number because (1 + 2 + 3 + 4 + 6 + 8 + 12) = 36

Deficient: aliquot sum < number
 8 is a deficient number because (1 + 2 + 4) = 7
 Prime numbers are deficient
Implement a way to determine whether a given number is perfect. Depending on your language track, you may also need to implement a way to determine whether a given number is abundant or deficient.
Rust Installation
Refer to the exercism help page for Rust installation and learning resources.
Writing the Code
Execute the tests with:
1 
$ cargo test

All but the first test have been ignored. After you get the first test to
pass, remove the ignore flag (#[ignore]
) from the next test and get the tests
to pass again. The test file is located in the tests
directory. You can
also remove the ignore flag from all the tests to get them to run all at once
if you wish.
Make sure to read the Modules chapter if you haven't already, it will help you with organizing your files.
Feedback, Issues, Pull Requests
The exercism/rust repository on GitHub is the home for all of the Rust exercises. If you have feedback about an exercise, or want to help implement new exercises, head over there and create an issue. Members of the rust track team are happy to help!
If you want to know more about Exercism, take a look at the contribution guide.
Source
Taken from Chapter 2 of Functional Thinking by Neal Ford. http://shop.oreilly.com/product/0636920029687.do
Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.