add resistor-color-duo

config.json

@@ -52,6 +52,14 @@
         "practices": [],
         "prerequisites": [],
         "difficulty": 2
+      },
+      {
+        "slug": "resistor-color-duo",
+        "name": "Resistor Color Duo",
+        "uuid": "01cf8fd2-3e48-4b2a-b06f-7a1fdc42d561",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2
       }
     ]
   },

exercises/practice/resistor-color-duo/.docs/instructions.md

@@ -0,0 +1,33 @@
+# Instructions
+
+If you want to build something using a Raspberry Pi, you'll probably use _resistors_.
+For this exercise, you need to know two things about them:
+
+- Each resistor has a resistance value.
+- Resistors are small - so small in fact that if you printed the resistance value on them, it would be hard to read.
+
+To get around this problem, manufacturers print color-coded bands onto the resistors to denote their resistance values.
+Each band has a position and a numeric value.
+
+The first 2 bands of a resistor have a simple encoding scheme: each color maps to a single number.
+For example, if they printed a brown band (value 1) followed by a green band (value 5), it would translate to the number 15.
+
+In this exercise you are going to create a helpful program so that you don't have to remember the values of the bands.
+The program will take color names as input and output a two digit number, even if the input is more than two colors!
+
+The band colors are encoded as follows:
+
+- black: 0
+- brown: 1
+- red: 2
+- orange: 3
+- yellow: 4
+- green: 5
+- blue: 6
+- violet: 7
+- grey: 8
+- white: 9
+
+From the example above:
+brown-green should return 15, and
+brown-green-violet should return 15 too, ignoring the third color.

exercises/practice/resistor-color-duo/.gitignore

@@ -0,0 +1,2 @@
+node_modules
+*/*.res.js

exercises/practice/resistor-color-duo/.meta/ResistorColorDuo.res

@@ -0,0 +1,49 @@
+type band =
+  | Black
+  | Brown
+  | Red
+  | Orange
+  | Yellow
+  | Green
+  | Blue
+  | Violet
+  | Grey
+  | White
+
+let bandToValue = (c: band) =>
+  switch c {
+  | Black => 0
+  | Brown => 1
+  | Red => 2
+  | Orange => 3
+  | Yellow => 4
+  | Green => 5
+  | Blue => 6
+  | Violet => 7
+  | Grey => 8
+  | White => 9
+  }
+
+let stringToBand = (s: string) =>
+  switch s {
+  | "black" => Black
+  | "brown" => Brown
+  | "red" => Red
+  | "orange" => Orange
+  | "yellow" => Yellow
+  | "green" => Green
+  | "blue" => Blue
+  | "violet" => Violet
+  | "grey" => Grey
+  | "white" => White
+  | _ => Black
+  }
+
+let transform = (opt: option<string>) =>
+  opt->Option.getOr("black")->stringToBand->bandToValue
+
+let value = (colors: array<string>) => {
+  let tens = transform(colors[0])
+  let ones = transform(colors[1])
+  tens * 10 + ones
+}

exercises/practice/resistor-color-duo/.meta/config.json

@@ -0,0 +1,22 @@
+{
+  "authors": [
+    "BNAndras"
+  ],
+  "files": {
+    "solution": [
+      "src/ResistorColorDuo.res"
+    ],
+    "test": [
+      "tests/ResistorColorDuo_test.res"
+    ],
+    "example": [
+      ".meta/ResistorColorDuo.res"
+    ],
+    "editor": [
+      "src/ResistorColorDuo.resi"
+    ]
+  },
+  "blurb": "Convert color codes, as used on resistors, to a numeric value.",
+  "source": "Maud de Vries, Erik Schierboom",
+  "source_url": "https://github.com/exercism/problem-specifications/issues/1464"
+}

exercises/practice/resistor-color-duo/.meta/testTemplate.js

@@ -0,0 +1,17 @@
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { intEqual } from "../../../../test_generator/assertions.js";
+import { generateTests } from '../../../../test_generator/testGenerator.js';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const slug = path.basename(path.resolve(__dirname, '..'))
+
+// EDIT THIS WITH YOUR ASSERTIONS
+export const assertionFunctions = [ intEqual ]
+
+// EDIT THIS WITH YOUR TEST TEMPLATES
+export const template = (c) => {
+  return `intEqual(~message="${c.description}", value(${JSON.stringify(c.input.colors)}), ${c.expected})`
+}
+
+generateTests(__dirname, slug, assertionFunctions, template)

exercises/practice/resistor-color-duo/.meta/tests.toml

@@ -0,0 +1,31 @@
+# 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.
+
+[ce11995a-5b93-4950-a5e9-93423693b2fc]
+description = "Brown and black"
+
+[7bf82f7a-af23-48ba-a97d-38d59406a920]
+description = "Blue and grey"
+
+[f1886361-fdfd-4693-acf8-46726fe24e0c]
+description = "Yellow and violet"
+
+[b7a6cbd2-ae3c-470a-93eb-56670b305640]
+description = "White and red"
+
+[77a8293d-2a83-4016-b1af-991acc12b9fe]
+description = "Orange and orange"
+
+[0c4fb44f-db7c-4d03-afa8-054350f156a8]
+description = "Ignore additional colors"
+
+[4a8ceec5-0ab4-4904-88a4-daf953a5e818]
+description = "Black and brown, one-digit"

exercises/practice/resistor-color-duo/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Exercism
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.