Add palindrome-products exercise

config.json

@@ -578,6 +578,14 @@
         "prerequisites": [],
         "difficulty": 6
       },
+      {
+        "slug": "palindrome-products",
+        "name": "Palindrome Products",
+        "uuid": "2810c41a-49c6-4db3-9afe-7f39bb2de651",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 6
+      },
       {
         "slug": "parallel-letter-frequency",
         "name": "Parallel Letter Frequency",

exercises/practice/palindrome-products/.docs/instructions.md

@@ -0,0 +1,36 @@
+# Instructions
+
+Detect palindrome products in a given range.
+
+A palindromic number is a number that remains the same when its digits are reversed.
+For example, `121` is a palindromic number but `112` is not.
+
+Given a range of numbers, find the largest and smallest palindromes which
+are products of two numbers within that range.
+
+Your solution should return the largest and smallest palindromes, along with the factors of each within the range.
+If the largest or smallest palindrome has more than one pair of factors within the range, then return all the pairs.
+
+## Example 1
+
+Given the range `[1, 9]` (both inclusive)...
+
+And given the list of all possible products within this range:
+`[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 15, 21, 24, 27, 20, 28, 32, 36, 25, 30, 35, 40, 45, 42, 48, 54, 49, 56, 63, 64, 72, 81]`
+
+The palindrome products are all single digit numbers (in this case):
+`[1, 2, 3, 4, 5, 6, 7, 8, 9]`
+
+The smallest palindrome product is `1`.
+Its factors are `(1, 1)`.
+The largest palindrome product is `9`.
+Its factors are `(1, 9)` and `(3, 3)`.
+
+## Example 2
+
+Given the range `[10, 99]` (both inclusive)...
+
+The smallest palindrome product is `121`.
+Its factors are `(11, 11)`.
+The largest palindrome product is `9009`.
+Its factors are `(91, 99)`.

exercises/practice/palindrome-products/.meta/config.json

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+{
+  "authors": [
+    "erikschierboom"
+  ],
+  "files": {
+    "solution": [
+      "palindrome-products.ua"
+    ],
+    "test": [
+      "tests.ua"
+    ],
+    "example": [
+      ".meta/example.ua"
+    ]
+  },
+  "blurb": "Detect palindrome products in a given range.",
+  "source": "Problem 4 at Project Euler",
+  "source_url": "https://projecteuler.net/problem=4"
+}

exercises/practice/palindrome-products/.meta/example.ua

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+IsPalindrome ← ≍⇌.°⋕
+Palindromes  ← ◌◌ ⍢(+1 ⨬(∘|⊃(⊙∘|⊂⊙◌)) ⊸IsPalindrome|≥) ⊙⊙[]
+Candidates   ← ⍜(--1)⇡ ∩(×.)
+
+Candidates  ← ⍜(--1)⇡ ∩(×.)
+Palindrome  ← ⍜(°⋕|⊂⟜⇌)
+Palindromes ← ≡Palindrome Candidates
+Factors ← (
+  ◡(⋅Candidates)
+  ◡÷
+  ◡(×⊃(
+      ⊙⋅⋅∘
+      :
+      ≥
+    | ⊙⋅⋅⋅∘
+      :
+      ≤
+    ))
+  ⊃(▽|▽⊙◌)
+  (=⌊.).
+  ⊃(▽|▽⊙◌)
+  ◴≡(⍆⊂)
+)
+
+Largest ← (
+  ◡Palindromes
+  ⍚Factors
+
+  /◇⊂⊸⍚(>0⧻)
+  ▽
+  ≡(⊂⊂◡× °⊂)°□⊣
+  ⊙⋅⋅⋅ # TODO: fix
+)
+Smallest ← (
+  ◡Palindromes
+  ⍚Factors
+
+  /◇⊂⊸⍚(>0⧻)
+  ▽
+  ≡(⊂⊂◡× °⊂)°□⊢
+  ⊙⋅⋅⋅ # TODO: fix
+)
+
+Candidates   ← ⍜(--1)⇡ ∩(×.)
+IsPalindrome ← ≍⇌.°⋕
+Palindromes  ← ▽⊸≡IsPalindrome Candidates
+
+# Palindrome  ← ⍜(°⋕|⊂⟜⇌)
+# Palindromes ← ≡Palindrome Candidates
+# Factors ← (
+# ◡(⋅Candidates)
+# ◡÷
+# ◡(×⊃(
+# ⊙⋅⋅∘
+# :
+# ≥
+# | ⊙⋅⋅⋅∘
+# :
+# ≤
+# ))
+# ⊃(▽|▽⊙◌)
+# (=⌊.).
+# ⊃(▽|▽⊙◌)
+# ◴≡(⍆⊂)
+# )
+
+# 100 999
+# 906609
+# Factors
+
+# Candidates 1 9
+
+Palindromes 1000 9999
+
+# IsPalindrome
+
+# ⍚Factors
+#
+# /◇⊂⊸⍚(>0⧻)
+# ▽
+# ≡(⊂⊂◡× °⊂)°□⊣
+# ⊙⋅⋅⋅ # TODO: fix
+#
+
+# https://www.uiua.org/pad?src=0_14_0-dev_7__Q2FuZGlkYXRlcyAgIOKGkCDijZwoLS0xKeKHoSDiiKkow5cuKQpJc1BhbGluZHJvbWUg4oaQIOKJjeKHjC7CsOKLlQpQYWxpbmRyb21lcyAg4oaQIOKWveKKuOKJoUlzUGFsaW5kcm9tZSBDYW5kaWRhdGVzCgojIFBhbGluZHJvbWUgIOKGkCDijZwowrDii5V84oqC4p-c4oeMKQojIFBhbGluZHJvbWVzIOKGkCDiiaFQYWxpbmRyb21lIENhbmRpZGF0ZXMKIyBGYWN0b3JzIOKGkCAoCiMg4pehKOKLhUNhbmRpZGF0ZXMpCiMg4pehw7cKIyDil6Eow5fiioMoCiMg4oqZ4ouF4ouF4oiYCiMgOgojIOKJpQojIHwg4oqZ4ouF4ouF4ouF4oiYCiMgOgojIOKJpAojICkpCiMg4oqDKOKWvXzilr3iipnil4wpCiMgKD3ijIouKS4KIyDiioMo4pa9fOKWveKKmeKXjCkKIyDil7TiiaEo4o2G4oqCKQojICkKCiMgMTAwIDk5OQojIDkwNjYwOQojIEZhY3RvcnMKCiMgQ2FuZGlkYXRlcyAxIDkKClBhbGluZHJvbWVzIDEwMDAgOTk5OQoKIyBJc1BhbGluZHJvbWUKCiMg4o2aRmFjdG9ycwojIAojIC_il4fiioLiirjijZooPjDip7spCiMg4pa9CiMg4omhKOKKguKKguKXocOXIMKw4oqCKcKw4pah4oqjCiMg4oqZ4ouF4ouF4ouFICMgVE9ETzogZml4CiMgCg==

exercises/practice/palindrome-products/.meta/tests.toml

@@ -0,0 +1,49 @@
+# 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.
+
+[5cff78fe-cf02-459d-85c2-ce584679f887]
+description = "find the smallest palindrome from single digit factors"
+
+[0853f82c-5fc4-44ae-be38-fadb2cced92d]
+description = "find the largest palindrome from single digit factors"
+
+[66c3b496-bdec-4103-9129-3fcb5a9063e1]
+description = "find the smallest palindrome from double digit factors"
+
+[a10682ae-530a-4e56-b89d-69664feafe53]
+description = "find the largest palindrome from double digit factors"
+
+[cecb5a35-46d1-4666-9719-fa2c3af7499d]
+description = "find the smallest palindrome from triple digit factors"
+
+[edab43e1-c35f-4ea3-8c55-2f31dddd92e5]
+description = "find the largest palindrome from triple digit factors"
+
+[4f802b5a-9d74-4026-a70f-b53ff9234e4e]
+description = "find the smallest palindrome from four digit factors"
+
+[787525e0-a5f9-40f3-8cb2-23b52cf5d0be]
+description = "find the largest palindrome from four digit factors"
+
+[58fb1d63-fddb-4409-ab84-a7a8e58d9ea0]
+description = "empty result for smallest if no palindrome in the range"
+
+[9de9e9da-f1d9-49a5-8bfc-3d322efbdd02]
+description = "empty result for largest if no palindrome in the range"
+
+[12e73aac-d7ee-4877-b8aa-2aa3dcdb9f8a]
+description = "error result for smallest if min is more than max"
+
+[eeeb5bff-3f47-4b1e-892f-05829277bd74]
+description = "error result for largest if min is more than max"
+
+[16481711-26c4-42e0-9180-e2e4e8b29c23]
+description = "smallest product does not use the smallest factor"

exercises/practice/palindrome-products/palindrome-products.ua

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+# Find the smallest palindrome product of two numbers in a range
+# PalindromeProducts ? Min Max
+Smallest ← |2 ⊙⋅(⍤ "Please implement Smallest" 0)
+
+# Find the largest palindrome product of two numbers in a range
+# PalindromeProducts ? Min Max
+Largest ← |2 ⊙⋅(⍤ "Please implement Largest" 0)

exercises/practice/palindrome-products/tests.ua

@@ -0,0 +1,47 @@
+~ "palindrome-products.ua" ~ Largest Smallest
+
+# Find the smallest palindrome from single digit factors
+Expected ← [1_1_1]
+⍤⤙≍ Expected Smallest 1 9
+
+# Find the largest palindrome from single digit factors
+Expected ← [9_1_9 9_3_3]
+⍤⤙≍ Expected Largest 1 9
+
+# Find the smallest palindrome from double digit factors
+Expected ← [121_11_11]
+⍤⤙≍ Expected Smallest 10 99
+
+# Find the largest palindrome from double digit factors
+Expected ← [9009_91_99]
+⍤⤙≍ Expected Largest 10 99
+
+# Find the smallest palindrome from triple digit factors
+Expected ← [10201_101_101]
+⍤⤙≍ Expected Smallest 100 999
+
+# Find the largest palindrome from triple digit factors
+Expected ← [906609_913_993]
+⍤⤙≍ Expected Largest 100 999
+
+# Find the smallest palindrome from four digit factors
+Expected ← [1002001_1001_1001]
+⍤⤙≍ Expected Smallest 1000 9999
+
+# Find the largest palindrome from four digit factors
+Expected ← [99000099_9901_9999]
+⍤⤙≍ Expected Largest 1000 9999
+
+# # Empty result for smallest if no palindrome in the range
+# Expected = (None_[]
+# ⍤⤙≍ Expected Smallest 1002 1003
+
+# # Empty result for largest if no palindrome in the range
+# Expected = (None_[]
+# ⍤⤙≍ Expected Largest 15 15
+
+# # Error result for smallest if min is more than max
+# (fun () -> smallest 10000 1 |> ignore) |> should throw typeof<System.ArgumentException>
+
+# # Error result for largest if min is more than max
+# (fun () -> largest 2 1 |> ignore) |> should throw typeof<System.ArgumentException>