feat: add roman-numerals exercise

config.json

@@ -577,6 +577,14 @@
         "prerequisites": [],
         "difficulty": 3
       },
+      {
+        "slug": "roman-numerals",
+        "name": "Roman Numerals",
+        "uuid": "eeab8f00-e9ac-4696-ba1d-d1c418199d5d",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "etl",
         "name": "ETL",

exercises/practice/roman-numerals/.docs/instructions.md

@@ -0,0 +1,47 @@
+# Instructions
+
+Write a function to convert from normal numbers to Roman Numerals.
+
+The Romans were a clever bunch.
+They conquered most of Europe and ruled it for hundreds of years.
+They invented concrete and straight roads and even bikinis.
+One thing they never discovered though was the number zero.
+This made writing and dating extensive histories of their exploits slightly more challenging, but the system of numbers they came up with is still in use today.
+For example the BBC uses Roman numerals to date their programs.
+
+The Romans wrote numbers using letters - I, V, X, L, C, D, M; notice these letters have lots of straight lines and are hence easy to hack into stone tablets.
+
+```text
+ 1  => I
+10  => X
+ 7  => VII
+```
+
+The maximum number supported by this notation is 3,999.
+
+Wikipedia says: Modern Roman numerals [...] are written by expressing each digit separately starting with the left most digit and skipping any digit with a value of zero.
+
+To see this in practice, consider the example of 1990.
+
+In Roman numerals 1990 is MCMXC:
+
+```text
+ 1000 => M
+  900 => CM
++  90 => XC
+----- => -----
+ 1990 => MCMXC
+```
+
+2008 is written as MMVIII:
+
+```text
+ 2000 => MM
++   8 => VIII
+----- => ------
+ 2008 => MMVIII
+```
+
+Learn more about [Roman numerals on Wikipedia][roman-numerals].
+
+[roman-numerals]: https://wiki.imperivm-romanvm.com/wiki/Roman_Numerals

exercises/practice/roman-numerals/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "keiravillekode"
+  ],
+  "files": {
+    "solution": [
+      "roman-numerals.v"
+    ],
+    "test": [
+      "run_test.v"
+    ],
+    "example": [
+      ".meta/example.v"
+    ]
+  },
+  "blurb": "Write a function to convert from normal numbers to Roman Numerals.",
+  "source": "The Roman Numeral Kata",
+  "source_url": "https://codingdojo.org/kata/RomanNumerals/"
+}

exercises/practice/roman-numerals/.meta/example.v

@@ -0,0 +1,30 @@
+module main
+
+const ones = [u8(`I`), `X`, `C`, `M`]
+
+const fives = [u8(`V`), `L`, `D`]
+
+fn write(mut buffer []u8, digit int, place int) {
+	if digit % 5 == 4 {
+		buffer << ones[place]
+		write(mut buffer, digit + 1, place)
+	} else if digit == 10 {
+		write(mut buffer, 1, place + 1)
+	} else if digit >= 5 {
+		buffer << fives[place]
+		write(mut buffer, digit - 5, place)
+	} else if digit > 0 {
+		buffer << ones[place]
+		write(mut buffer, digit - 1, place)
+	}
+}
+
+fn roman(number int) string {
+	assert number < 4000
+	mut buffer := []u8{}
+	write(mut buffer, number / 1000, 3)
+	write(mut buffer, number / 100 % 10, 2)
+	write(mut buffer, number / 10 % 10, 1)
+	write(mut buffer, number % 10, 0)
+	return buffer.bytestr()
+}

exercises/practice/roman-numerals/.meta/tests.toml

@@ -0,0 +1,81 @@
+# This is an auto-generated file. Regular comments will be removed when this
+# file is regenerated. Regenerating will not touch any manually added keys,
+# so comments can be added in a "comment" key.
+
+[19828a3a-fbf7-4661-8ddd-cbaeee0e2178]
+description = "1 is I"
+
+[f088f064-2d35-4476-9a41-f576da3f7b03]
+description = "2 is II"
+
+[b374a79c-3bea-43e6-8db8-1286f79c7106]
+description = "3 is III"
+
+[05a0a1d4-a140-4db1-82e8-fcc21fdb49bb]
+description = "4 is IV"
+
+[57c0f9ad-5024-46ab-975d-de18c430b290]
+description = "5 is V"
+
+[20a2b47f-e57f-4797-a541-0b3825d7f249]
+description = "6 is VI"
+
+[ff3fb08c-4917-4aab-9f4e-d663491d083d]
+description = "9 is IX"
+
+[6d1d82d5-bf3e-48af-9139-87d7165ed509]
+description = "16 is XVI"
+
+[2bda64ca-7d28-4c56-b08d-16ce65716cf6]
+description = "27 is XXVII"
+
+[a1f812ef-84da-4e02-b4f0-89c907d0962c]
+description = "48 is XLVIII"
+
+[607ead62-23d6-4c11-a396-ef821e2e5f75]
+description = "49 is XLIX"
+
+[d5b283d4-455d-4e68-aacf-add6c4b51915]
+description = "59 is LIX"
+
+[4465ffd5-34dc-44f3-ada5-56f5007b6dad]
+description = "66 is LXVI"
+
+[46b46e5b-24da-4180-bfe2-2ef30b39d0d0]
+description = "93 is XCIII"
+
+[30494be1-9afb-4f84-9d71-db9df18b55e3]
+description = "141 is CXLI"
+
+[267f0207-3c55-459a-b81d-67cec7a46ed9]
+description = "163 is CLXIII"
+
+[902ad132-0b4d-40e3-8597-ba5ed611dd8d]
+description = "166 is CLXVI"
+
+[cdb06885-4485-4d71-8bfb-c9d0f496b404]
+description = "402 is CDII"
+
+[6b71841d-13b2-46b4-ba97-dec28133ea80]
+description = "575 is DLXXV"
+
+[dacb84b9-ea1c-4a61-acbb-ce6b36674906]
+description = "666 is DCLXVI"
+
+[432de891-7fd6-4748-a7f6-156082eeca2f]
+description = "911 is CMXI"
+
+[e6de6d24-f668-41c0-88d7-889c0254d173]
+description = "1024 is MXXIV"
+
+[efbe1d6a-9f98-4eb5-82bc-72753e3ac328]
+description = "1666 is MDCLXVI"
+
+[bb550038-d4eb-4be2-a9ce-f21961ac3bc6]
+description = "3000 is MMM"
+
+[3bc4b41c-c2e6-49d9-9142-420691504336]
+description = "3001 is MMMI"
+
+[4e18e96b-5fbb-43df-a91b-9cb511fe0856]
+description = "3999 is MMMCMXCIX"

exercises/practice/roman-numerals/roman-numerals.v

@@ -0,0 +1,4 @@
+module main
+
+fn roman(number int) string {
+}

exercises/practice/roman-numerals/run_test.v

@@ -0,0 +1,105 @@
+module main
+
+fn test_1_is_i() {
+	assert roman(1) == 'I'
+}
+
+fn test_2_is_ii() {
+	assert roman(2) == 'II'
+}
+
+fn test_3_is_iii() {
+	assert roman(3) == 'III'
+}
+
+fn test_4_is_iv() {
+	assert roman(4) == 'IV'
+}
+
+fn test_5_is_v() {
+	assert roman(5) == 'V'
+}
+
+fn test_6_is_vi() {
+	assert roman(6) == 'VI'
+}
+
+fn test_9_is_ix() {
+	assert roman(9) == 'IX'
+}
+
+fn test_16_is_xvi() {
+	assert roman(16) == 'XVI'
+}
+
+fn test_27_is_xxvii() {
+	assert roman(27) == 'XXVII'
+}
+
+fn test_48_is_xlviii() {
+	assert roman(48) == 'XLVIII'
+}
+
+fn test_49_is_xlix() {
+	assert roman(49) == 'XLIX'
+}
+
+fn test_59_is_lix() {
+	assert roman(59) == 'LIX'
+}
+
+fn test_66_is_lxvi() {
+	assert roman(66) == 'LXVI'
+}
+
+fn test_93_is_xciii() {
+	assert roman(93) == 'XCIII'
+}
+
+fn test_141_is_cxli() {
+	assert roman(141) == 'CXLI'
+}
+
+fn test_163_is_clxiii() {
+	assert roman(163) == 'CLXIII'
+}
+
+fn test_166_is_clxvi() {
+	assert roman(166) == 'CLXVI'
+}
+
+fn test_402_is_cdii() {
+	assert roman(402) == 'CDII'
+}
+
+fn test_575_is_dlxxv() {
+	assert roman(575) == 'DLXXV'
+}
+
+fn test_666_is_dclxvi() {
+	assert roman(666) == 'DCLXVI'
+}
+
+fn test_911_is_cmxi() {
+	assert roman(911) == 'CMXI'
+}
+
+fn test_1024_is_mxxiv() {
+	assert roman(1024) == 'MXXIV'
+}
+
+fn test_1666_is_mdclxvi() {
+	assert roman(1666) == 'MDCLXVI'
+}
+
+fn test_3000_is_mmm() {
+	assert roman(3000) == 'MMM'
+}
+
+fn test_3001_is_mmmi() {
+	assert roman(3001) == 'MMMI'
+}
+
+fn test_3999_is_mmmcmxcix() {
+	assert roman(3999) == 'MMMCMXCIX'
+}