mirror of
https://github.com/correl/elm.git
synced 2024-11-25 03:00:06 +00:00
50 lines
1.3 KiB
Markdown
50 lines
1.3 KiB
Markdown
|
# Difference Of Squares
|
||
|
|
||
|
Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.
|
||
|
|
||
|
The square of the sum of the first ten natural numbers is
|
||
|
(1 + 2 + ... + 10)² = 55² = 3025.
|
||
|
|
||
|
The sum of the squares of the first ten natural numbers is
|
||
|
1² + 2² + ... + 10² = 385.
|
||
|
|
||
|
Hence the difference between the square of the sum of the first
|
||
|
ten natural numbers and the sum of the squares of the first ten
|
||
|
natural numbers is 3025 - 385 = 2640.
|
||
|
|
||
|
## Elm Installation
|
||
|
|
||
|
Refer to the [Exercism help page](http://exercism.io/languages/elm) for Elm
|
||
|
installation and learning resources.
|
||
|
|
||
|
## Writing the Code
|
||
|
|
||
|
The first time you start an exercise, you'll need to ensure you have the
|
||
|
appropriate dependencies installed.
|
||
|
|
||
|
```bash
|
||
|
$ npm install
|
||
|
```
|
||
|
|
||
|
Execute the tests with:
|
||
|
|
||
|
```bash
|
||
|
$ npm test
|
||
|
```
|
||
|
|
||
|
Automatically run tests again when you save changes:
|
||
|
|
||
|
```bash
|
||
|
$ npm run watch
|
||
|
```
|
||
|
|
||
|
As you work your way through the test suite, be sure to remove the `skip <|`
|
||
|
calls from each test until you get them all passing!
|
||
|
|
||
|
## Source
|
||
|
|
||
|
Problem 6 at Project Euler [http://projecteuler.net/problem=6](http://projecteuler.net/problem=6)
|
||
|
|
||
|
## Submitting Incomplete Solutions
|
||
|
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
|