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Published at Aug 26 2019
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Instructions

Test suite

Solution

Given a string of digits, output all the contiguous substrings of length `n`

in
that string.

For example, the string "49142" has the following 3-digit series:

- 491
- 914
- 142

And the following 4-digit series:

- 4914
- 9142

And if you ask for a 6-digit series from a 5-digit string, you deserve whatever you get.

Note that these series are only required to occupy *adjacent positions*
in the input; the digits need not be *numerically consecutive*.

The Scala exercises assume an SBT project scheme. The exercise solution source should be placed within the exercise directory/src/main/scala. The exercise unit tests can be found within the exercise directory/src/test/scala.

To run the tests simply run the command `sbt test`

in the exercise directory.

For more detailed info about the Scala track see the help page.

A subset of the Problem 8 at Project Euler http://projecteuler.net/problem=8

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

```
import org.scalatest.{Matchers, FunSuite}
/** @version created manually **/
class SeriesTest extends FunSuite with Matchers {
test("slices of one") {
Series.slices(1, "") should be (List())
Series.slices(1, "01234") should be (List(List(0), List(1), List(2),
List(3), List(4)))
}
test("slices of two") {
pending
Series.slices(2, "") should be (List())
Series.slices(2, "01") should be (List(List(0, 1)))
Series.slices(2, "01234") should be (List(List(0, 1), List(1, 2), List(2, 3),
List(3, 4)))
}
test("slices of three") {
pending
Series.slices(3, "") should be (List())
Series.slices(3, "012") should be (List(List(0, 1, 2)))
Series.slices(3, "01234") should be (List(List(0, 1, 2), List(1, 2, 3),
List(2, 3, 4)))
}
}
```

```
object Series {
def slices(count: Int, number: String) = number map (_.asDigit) sliding (count) toList
}
```

A huge amount can be learned from reading other peopleâ€™s code. This is why we wanted to give exercism users the option of making their solutions public.

Here are some questions to help you reflect on this solution and learn the most from it.

- What compromises have been made?
- Are there new concepts here that you could read more about to improve your understanding?

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