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Add largest-series-product (exercism#201)
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‎config.json

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"prerequisites": [],
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"difficulty": 3
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},
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{
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"slug": "largest-series-product",
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"name": "Largest Series Product",
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"uuid": "e3d2e2d5-bd70-42b8-8d61-871af9b16679",
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"practices": [],
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"prerequisites": [],
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"difficulty": 3
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},
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{
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"slug": "custom-set",
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"name": "Custom Set",

‎exercises/practice/largest-series-product/.docs/instructions.md

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# Instructions
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Your task is to look for patterns in the long sequence of digits in the encrypted signal.
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The technique you're going to use here is called the largest series product.
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Let's define a few terms, first.
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- **input**: the sequence of digits that you need to analyze
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- **series**: a sequence of adjacent digits (those that are next to each other) that is contained within the input
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- **span**: how many digits long each series is
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- **product**: what you get when you multiply numbers together
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Let's work through an example, with the input `"63915"`.
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- To form a series, take adjacent digits in the original input.
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- If you are working with a span of `3`, there will be three possible series:
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- `"639"`
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- `"391"`
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- `"915"`
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- Then we need to calculate the product of each series:
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- The product of the series `"639"` is 162 (`6 × 3 × 9 = 162`)
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- The product of the series `"391"` is 27 (`3 × 9 × 1 = 27`)
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- The product of the series `"915"` is 45 (`9 × 1 × 5 = 45`)
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- 162 is bigger than both 27 and 45, so the largest series product of `"63915"` is from the series `"639"`.
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So the answer is **162**.

‎exercises/practice/largest-series-product/.docs/introduction.md

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# Introduction
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You work for a government agency that has intercepted a series of encrypted communication signals from a group of bank robbers.
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The signals contain a long sequence of digits.
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Your team needs to use various digital signal processing techniques to analyze the signals and identify any patterns that may indicate the planning of a heist.

‎exercises/practice/largest-series-product/.meta/config.json

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{
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"authors": [
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"glennj"
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],
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"files": {
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"solution": [
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"largest-series-product.wren"
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],
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"test": [
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"largest-series-product.spec.wren"
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],
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"example": [
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".meta/proof.ci.wren"
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]
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},
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"blurb": "Given a string of digits, calculate the largest product for a contiguous substring of digits of length n.",
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"source": "A variation on Problem 8 at Project Euler",
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"source_url": "https://projecteuler.net/problem=8"
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}

‎exercises/practice/largest-series-product/.meta/proof.ci.wren

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class Series {
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construct new(series, span) {
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_span = span
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_digits = series.codePoints.map {|cp| cp - 48}.toList
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if (_span < 0) {
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Fiber.abort("span must not be negative")
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}
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if (_span > series.count) {
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Fiber.abort("span must be smaller than string length")
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}
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if (_digits.any {|d| d < 0 || d > 9}) {
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Fiber.abort("digits input must only contain digits")
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}
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}
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largestProduct {
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var indices = 0..(_digits.count - _span)
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var products = indices.map {|i| product_(_digits[i...(i + _span)])}
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return max_(products)
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}
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product_(list) { list.reduce(1) {|prod, num| prod * num} }
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max_(list) { list.reduce(0) {|max, prod| max.max(prod)} }
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}

‎exercises/practice/largest-series-product/.meta/tests.toml

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# This is an auto-generated file.
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#
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# Regenerating this file via `configlet sync` will:
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# - Recreate every `description` key/value pair
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# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
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# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
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# - Preserve any other key/value pair
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#
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# As user-added comments (using the # character) will be removed when this file
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# is regenerated, comments can be added via a `comment` key.
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[7c82f8b7-e347-48ee-8a22-f672323324d4]
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description = "finds the largest product if span equals length"
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[88523f65-21ba-4458-a76a-b4aaf6e4cb5e]
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description = "can find the largest product of 2 with numbers in order"
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[f1376b48-1157-419d-92c2-1d7e36a70b8a]
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description = "can find the largest product of 2"
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[46356a67-7e02-489e-8fea-321c2fa7b4a4]
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description = "can find the largest product of 3 with numbers in order"
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[a2dcb54b-2b8f-4993-92dd-5ce56dece64a]
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description = "can find the largest product of 3"
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[673210a3-33cd-4708-940b-c482d7a88f9d]
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description = "can find the largest product of 5 with numbers in order"
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[02acd5a6-3bbf-46df-8282-8b313a80a7c9]
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description = "can get the largest product of a big number"
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[76dcc407-21e9-424c-a98e-609f269622b5]
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description = "reports zero if the only digits are zero"
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[6ef0df9f-52d4-4a5d-b210-f6fae5f20e19]
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description = "reports zero if all spans include zero"
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[5d81aaf7-4f67-4125-bf33-11493cc7eab7]
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description = "rejects span longer than string length"
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[06bc8b90-0c51-4c54-ac22-3ec3893a079e]
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description = "reports 1 for empty string and empty product (0 span)"
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[3ec0d92e-f2e2-4090-a380-70afee02f4c0]
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description = "reports 1 for nonempty string and empty product (0 span)"
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[6d96c691-4374-4404-80ee-2ea8f3613dd4]
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description = "rejects empty string and nonzero span"
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[7a38f2d6-3c35-45f6-8d6f-12e6e32d4d74]
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description = "rejects invalid character in digits"
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[5fe3c0e5-a945-49f2-b584-f0814b4dd1ef]
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description = "rejects negative span"
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include = false
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[c859f34a-9bfe-4897-9c2f-6d7f8598e7f0]
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description = "rejects negative span"
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reimplements = "5fe3c0e5-a945-49f2-b584-f0814b4dd1ef"

‎exercises/practice/largest-series-product/LICENSE

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MIT License
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Copyright (c) 2024 Exercism
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.

‎exercises/practice/largest-series-product/largest-series-product.spec.wren

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import "./largest-series-product" for Series
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import "wren-testie/testie" for Testie, Expect
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Testie.test("LargestSeriesProduct") { |do, skip|
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do.test("finds the largest product if span equals length") {
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var actual = Series.new("29", 2).largestProduct
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var expected = 18
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Expect.value(actual).toEqual(expected)
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}
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skip.test("can find the largest product of 2 with numbers in order") {
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var actual = Series.new("0123456789", 2).largestProduct
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var expected = 72
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Expect.value(actual).toEqual(expected)
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}
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skip.test("can find the largest product of 2") {
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var actual = Series.new("576802143", 2).largestProduct
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var expected = 48
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Expect.value(actual).toEqual(expected)
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}
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skip.test("can find the largest product of 3 with numbers in order") {
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var actual = Series.new("0123456789", 3).largestProduct
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var expected = 504
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Expect.value(actual).toEqual(expected)
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}
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skip.test("can find the largest product of 3") {
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var actual = Series.new("1027839564", 3).largestProduct
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var expected = 270
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Expect.value(actual).toEqual(expected)
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}
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skip.test("can find the largest product of 5 with numbers in order") {
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var actual = Series.new("0123456789", 5).largestProduct
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var expected = 15120
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Expect.value(actual).toEqual(expected)
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}
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skip.test("can get the largest product of a big number") {
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var actual = Series.new("73167176531330624919225119674426574742355349194934", 6).largestProduct
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var expected = 23520
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Expect.value(actual).toEqual(expected)
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}
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skip.test("reports zero if the only digits are zero") {
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var actual = Series.new("0000", 2).largestProduct
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var expected = 0
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Expect.value(actual).toEqual(expected)
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}
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skip.test("reports zero if all spans include zero") {
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var actual = Series.new("99099", 3).largestProduct
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var expected = 0
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Expect.value(actual).toEqual(expected)
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}
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skip.test("rejects span longer than string length") {
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Expect.that {
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Series.new("123", 4).largestProduct
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}.abortsWith("span must be smaller than string length")
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}
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skip.test("reports 1 for empty string and empty product (0 span)") {
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var actual = Series.new("", 0).largestProduct
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var expected = 1
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Expect.value(actual).toEqual(expected)
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}
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skip.test("reports 1 for nonempty string and empty product (0 span)") {
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var actual = Series.new("123", 0).largestProduct
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var expected = 1
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Expect.value(actual).toEqual(expected)
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}
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skip.test("rejects empty string and nonzero span") {
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Expect.that {
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Series.new("", 1).largestProduct
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}.abortsWith("span must be smaller than string length")
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}
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skip.test("rejects invalid character in digits") {
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Expect.that {
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Series.new("1234a5", 2).largestProduct
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}.abortsWith("digits input must only contain digits")
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}
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skip.test("rejects negative span") {
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Expect.that {
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Series.new("12345", -1).largestProduct
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}.abortsWith("span must not be negative")
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}
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}

‎exercises/practice/largest-series-product/largest-series-product.wren

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class Series {
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construct new() {
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Fiber.abort("Remove this statement and implement this function")
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}
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}

‎exercises/practice/largest-series-product/package.wren

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import "wren-package" for WrenPackage, Dependency
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import "os" for Process
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class Package is WrenPackage {
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construct new() {}
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name { "exercism/largest-series-product" }
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dependencies {
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return [
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Dependency.new("wren-testie", "0.3.0", "https://github.com/joshgoebel/wren-testie.git")
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]
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}
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}
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Package.new().default()

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