Add practice exercise: sum-of-multiples

config.json

@@ -258,6 +258,14 @@
         "prerequisites": [],
         "difficulty": 5
       },
+      {
+        "slug": "sum-of-multiples",
+        "name": "Sum of Multiples",
+        "uuid": "18ea92e5-6855-4dd6-b6d0-e2473d036fd4",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 5
+      },
       {
         "slug": "swift-scheduling",
         "name": "Swift Scheduling",

exercises/practice/sum-of-multiples/.docs/instructions.append.md

@@ -0,0 +1,7 @@
+# SQLite-specific instructions
+
+## JSON documentation
+
+[JSON Functions And Operators][json-docs]
+
+[json-docs]: https://www.sqlite.org/json1.html

exercises/practice/sum-of-multiples/.docs/instructions.md

@@ -0,0 +1,27 @@
+# Instructions
+
+Your task is to write the code that calculates the energy points that get awarded to players when they complete a level.
+
+The points awarded depend on two things:
+
+- The level (a number) that the player completed.
+- The base value of each magical item collected by the player during that level.
+
+The energy points are awarded according to the following rules:
+
+1. For each magical item, take the base value and find all the multiples of that value that are less than the level number.
+2. Combine the sets of numbers.
+3. Remove any duplicates.
+4. Calculate the sum of all the numbers that are left.
+
+Let's look at an example:
+
+**The player completed level 20 and found two magical items with base values of 3 and 5.**
+
+To calculate the energy points earned by the player, we need to find all the unique multiples of these base values that are less than level 20.
+
+- Multiples of 3 less than 20: `{3, 6, 9, 12, 15, 18}`
+- Multiples of 5 less than 20: `{5, 10, 15}`
+- Combine the sets and remove duplicates: `{3, 5, 6, 9, 10, 12, 15, 18}`
+- Sum the unique multiples: `3 + 5 + 6 + 9 + 10 + 12 + 15 + 18 = 78`
+- Therefore, the player earns **78** energy points for completing level 20 and finding the two magical items with base values of 3 and 5.

exercises/practice/sum-of-multiples/.docs/introduction.md

@@ -0,0 +1,6 @@
+# Introduction
+
+You work for a company that makes an online, fantasy-survival game.
+
+When a player finishes a level, they are awarded energy points.
+The amount of energy awarded depends on which magical items the player found while exploring that level.

exercises/practice/sum-of-multiples/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "jimmytty"
+  ],
+  "files": {
+    "solution": [
+      "sum-of-multiples.sql"
+    ],
+    "test": [
+      "sum-of-multiples_test.sql"
+    ],
+    "example": [
+      ".meta/example.sql"
+    ]
+  },
+  "blurb": "Given a number, find the sum of all the multiples of particular numbers up to but not including that number.",
+  "source": "A variation on Problem 1 at Project Euler",
+  "source_url": "https://projecteuler.net/problem=1"
+}

exercises/practice/sum-of-multiples/.meta/example.sql

@@ -0,0 +1,14 @@
+UPDATE "sum-of-multiples"
+   SET result = (
+     WITH sets (multiples) AS (
+       SELECT (
+         SELECT JSON_GROUP_ARRAY(s.value)
+           FROM GENERATE_SERIES(1, "limit" - 1) s
+          WHERE s.value % j.value = 0
+       )
+         FROM JSON_EACH(factors) j
+     )
+     SELECT COALESCE(SUM(DISTINCT(j.value)), 0)
+       FROM sets, JSON_EACH(multiples) j
+   )
+;

exercises/practice/sum-of-multiples/.meta/tests.toml

@@ -0,0 +1,58 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[54aaab5a-ce86-4edc-8b40-d3ab2400a279]
+description = "no multiples within limit"
+
+[361e4e50-c89b-4f60-95ef-5bc5c595490a]
+description = "one factor has multiples within limit"
+
+[e644e070-040e-4ae0-9910-93c69fc3f7ce]
+description = "more than one multiple within limit"
+
+[607d6eb9-535c-41ce-91b5-3a61da3fa57f]
+description = "more than one factor with multiples within limit"
+
+[f47e8209-c0c5-4786-b07b-dc273bf86b9b]
+description = "each multiple is only counted once"
+
+[28c4b267-c980-4054-93e9-07723db615ac]
+description = "a much larger limit"
+
+[09c4494d-ff2d-4e0f-8421-f5532821ee12]
+description = "three factors"
+
+[2d0d5faa-f177-4ad6-bde9-ebb865083751]
+description = "factors not relatively prime"
+
+[ece8f2e8-96aa-4166-bbb7-6ce71261e354]
+description = "some pairs of factors relatively prime and some not"
+
+[624fdade-6ffb-400e-8472-456a38c171c0]
+description = "one factor is a multiple of another"
+
+[949ee7eb-db51-479c-b5cb-4a22b40ac057]
+description = "much larger factors"
+
+[41093673-acbd-482c-ab80-d00a0cbedecd]
+description = "all numbers are multiples of 1"
+
+[1730453b-baaa-438e-a9c2-d754497b2a76]
+description = "no factors means an empty sum"
+
+[214a01e9-f4bf-45bb-80f1-1dce9fbb0310]
+description = "the only multiple of 0 is 0"
+
+[c423ae21-a0cb-4ec7-aeb1-32971af5b510]
+description = "the factor 0 does not affect the sum of multiples of other factors"
+
+[17053ba9-112f-4ac0-aadb-0519dd836342]
+description = "solutions using include-exclude must extend to cardinality greater than 3"

exercises/practice/sum-of-multiples/create_fixture.sql

@@ -0,0 +1,11 @@
+DROP TABLE IF EXISTS "sum-of-multiples";
+CREATE TABLE "sum-of-multiples" (
+    factors TEXT    NOT NULL,     -- json array of integers
+    "limit" INTEGER NOT NULL,
+    result  INTEGER
+);
+
+.mode csv
+.import ./data.csv "sum-of-multiples"
+
+UPDATE "sum-of-multiples" SET result = NULL;

exercises/practice/sum-of-multiples/create_test_table.sql

@@ -0,0 +1,35 @@
+DROP TABLE IF EXISTS tests;
+CREATE TABLE IF NOT EXISTS tests (
+    -- uuid and description are taken from the test.toml file
+    uuid TEXT PRIMARY KEY,
+    description TEXT NOT NULL,
+    -- The following section is needed by the online test-runner
+    status TEXT DEFAULT 'fail',
+    message TEXT,
+    output TEXT,
+    test_code TEXT,
+    task_id INTEGER DEFAULT NULL,
+    -- Here are columns for the actual tests
+    factors TEXT NOT NULL,      -- json array of integers
+    "limit" INTEGER NOT NULL,
+    expected INTEGER NOT NULL
+);
+
+INSERT INTO tests (uuid, description, factors, "limit", expected)
+    VALUES
+        ('54aaab5a-ce86-4edc-8b40-d3ab2400a279', 'no multiples within limit', '[3,5]', 1, 0),
+        ('361e4e50-c89b-4f60-95ef-5bc5c595490a', 'one factor has multiples within limit', '[3,5]', 4, 3),
+        ('e644e070-040e-4ae0-9910-93c69fc3f7ce', 'more than one multiple within limit', '[3]', 7, 9),
+        ('607d6eb9-535c-41ce-91b5-3a61da3fa57f', 'more than one factor with multiples within limit', '[3,5]', 10, 23),
+        ('f47e8209-c0c5-4786-b07b-dc273bf86b9b', 'each multiple is only counted once', '[3,5]', 100, 2318),
+        ('28c4b267-c980-4054-93e9-07723db615ac', 'a much larger limit', '[3,5]', 1000, 233168),
+        ('09c4494d-ff2d-4e0f-8421-f5532821ee12', 'three factors', '[7,13,17]', 20, 51),
+        ('2d0d5faa-f177-4ad6-bde9-ebb865083751', 'factors not relatively prime', '[4,6]', 15, 30),
+        ('ece8f2e8-96aa-4166-bbb7-6ce71261e354', 'some pairs of factors relatively prime and some not', '[5,6,8]', 150, 4419),
+        ('624fdade-6ffb-400e-8472-456a38c171c0', 'one factor is a multiple of another', '[5,25]', 51, 275),
+        ('949ee7eb-db51-479c-b5cb-4a22b40ac057', 'much larger factors', '[43,47]', 10000, 2203160),
+        ('41093673-acbd-482c-ab80-d00a0cbedecd', 'all numbers are multiples of 1', '[1]', 100, 4950),
+        ('1730453b-baaa-438e-a9c2-d754497b2a76', 'no factors means an empty sum', '[]', 10000, 0),
+        ('214a01e9-f4bf-45bb-80f1-1dce9fbb0310', 'the only multiple of 0 is 0', '[0]', 1, 0),
+        ('c423ae21-a0cb-4ec7-aeb1-32971af5b510', 'the factor 0 does not affect the sum of multiples of other factors', '[3,0]', 4, 3),
+        ('17053ba9-112f-4ac0-aadb-0519dd836342', 'solutions using include-exclude must extend to cardinality greater than 3', '[2,3,5,7,11]', 10000, 39614537);

exercises/practice/sum-of-multiples/data.csv

@@ -0,0 +1,16 @@
+"[3,5]",1,
+"[3,5]",4,
+"[3]",7,
+"[3,5]",10,
+"[3,5]",100,
+"[3,5]",1000,
+"[7,13,17]",20,
+"[4,6]",15,
+"[5,6,8]",150,
+"[5,25]",51,
+"[43,47]",10000,
+"[1]",100,
+"[]",10000,
+"[0]",1,
+"[3,0]",4,
+"[2,3,5,7,11]",10000,

exercises/practice/sum-of-multiples/sum-of-multiples.sql

@@ -0,0 +1,8 @@
+-- Schema:
+-- CREATE TABLE "sum-of-multiples" (
+--     factors TEXT    NOT NULL,     -- json array of integers
+--     "limit" INTEGER NOT NULL,
+--     result  INTEGER
+-- );
+--
+-- Task: update the "sum-of-multiples" table and set the result based on the phrase.

exercises/practice/sum-of-multiples/sum-of-multiples_test.sql

@@ -0,0 +1,40 @@
+-- Create database:
+.read ./create_fixture.sql
+
+-- Read user student solution and save any output as markdown in user_output.md:
+.mode markdown
+.output user_output.md
+.read ./sum-of-multiples.sql
+.output
+
+-- Create a clean testing environment:
+.read ./create_test_table.sql
+
+-- Comparison of user input and the tests updates the status for each test:
+UPDATE tests
+SET status = 'pass'
+FROM (SELECT factors, "limit", result FROM "sum-of-multiples") AS actual
+WHERE (actual.factors, actual."limit", actual.result) = (tests.factors, tests."limit", tests.expected);
+
+-- Update message for failed tests to give helpful information:
+UPDATE tests
+SET message = (
+    'Result for "'
+    || PRINTF('factors=%s, limit=%d', tests.factors, tests."limit")
+    || '"'
+    || ' is <' || COALESCE(actual.result, 'NULL')
+    || '> but should be <' || tests.expected || '>'
+)
+FROM (SELECT factors, "limit", result FROM "sum-of-multiples") AS actual
+WHERE (actual.factors, actual."limit") = (tests.factors, tests."limit") AND tests.status = 'fail';
+
+-- Save results to ./output.json (needed by the online test-runner)
+.mode json
+.once './output.json'
+SELECT description, status, message, output, test_code, task_id
+FROM tests;
+
+-- Display test results in readable form for the student:
+.mode table
+SELECT description, status, message
+FROM tests;