Add queen-attack exercise

config.json

@@ -553,6 +553,14 @@
         "practices": [],
         "prerequisites": [],
         "difficulty": 9
+      },
+      {
+        "slug": "queen-attack",
+        "name": "Queen Attack",
+        "uuid": "b1e4dd71-27e8-4ba6-af6b-5c0ad8a11df5",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
       }
     ]
   },

exercises/practice/queen-attack/.docs/instructions.append.md

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+# Instructions append
+
+This exercises uses [modules as functions](https://www.uiua.org/tutorial/modules#modules-as-functions) for a nice way to group functions that work on the same type of data (queens on a chessboard in this case).

exercises/practice/queen-attack/.docs/instructions.md

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+# Instructions
+
+Given the position of two queens on a chess board, indicate whether or not they are positioned so that they can attack each other.
+
+In the game of chess, a queen can attack pieces which are on the same row, column, or diagonal.
+
+A chessboard can be represented by an 8 by 8 array.
+
+So if you are told the white queen is at `c5` (zero-indexed at column 2, row 3) and the black queen at `f2` (zero-indexed at column 5, row 6), then you know that the set-up is like so:
+
+![A chess board with two queens. Arrows emanating from the queen at c5 indicate possible directions of capture along file, rank and diagonal.](https://assets.exercism.org/images/exercises/queen-attack/queen-capture.svg)
+
+You are also able to answer whether the queens can attack each other.
+In this case, that answer would be yes, they can, because both pieces share a diagonal.
+
+## Credit
+
+The chessboard image was made by [habere-et-dispertire][habere-et-dispertire] using LaTeX and the [chessboard package][chessboard-package] by Ulrike Fischer.
+
+[habere-et-dispertire]: https://exercism.org/profiles/habere-et-dispertire
+[chessboard-package]: https://github.com/u-fischer/chessboard

exercises/practice/queen-attack/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "erikschierboom"
+  ],
+  "files": {
+    "solution": [
+      "queen-attack.ua"
+    ],
+    "test": [
+      "tests.ua"
+    ],
+    "example": [
+      ".meta/example.ua"
+    ]
+  },
+  "blurb": "Given the position of two queens on a chess board, indicate whether or not they are positioned so that they can attack each other.",
+  "source": "J Dalbey's Programming Practice problems",
+  "source_url": "https://users.csc.calpoly.edu/~jdalbey/103/Projects/ProgrammingPractice.html"
+}

exercises/practice/queen-attack/.meta/example.ua

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+┌─╴Queen
+  Valid     ← ×⊓≥≤0,7
+  New       ← ⊟⊓(⍤"invalid row" Valid.|⍤"invalid column" Valid.)
+  Row       ← ⊢
+  Column    ← ⊣
+  CanAttack ← ↥↥⊃(=|⋅⋅=|=⊙(⌵-)⌵-) ⊃(∩Row|∩Column)
+└─╴

exercises/practice/queen-attack/.meta/tests.toml

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+# 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.
+
+[3ac4f735-d36c-44c4-a3e2-316f79704203]
+description = "Test creation of Queens with valid and invalid positions -> queen with a valid position"
+
+[4e812d5d-b974-4e38-9a6b-8e0492bfa7be]
+description = "Test creation of Queens with valid and invalid positions -> queen must have positive row"
+
+[f07b7536-b66b-4f08-beb9-4d70d891d5c8]
+description = "Test creation of Queens with valid and invalid positions -> queen must have row on board"
+
+[15a10794-36d9-4907-ae6b-e5a0d4c54ebe]
+description = "Test creation of Queens with valid and invalid positions -> queen must have positive column"
+
+[6907762d-0e8a-4c38-87fb-12f2f65f0ce4]
+description = "Test creation of Queens with valid and invalid positions -> queen must have column on board"
+
+[33ae4113-d237-42ee-bac1-e1e699c0c007]
+description = "Test the ability of one queen to attack another -> cannot attack"
+
+[eaa65540-ea7c-4152-8c21-003c7a68c914]
+description = "Test the ability of one queen to attack another -> can attack on same row"
+
+[bae6f609-2c0e-4154-af71-af82b7c31cea]
+description = "Test the ability of one queen to attack another -> can attack on same column"
+
+[0e1b4139-b90d-4562-bd58-dfa04f1746c7]
+description = "Test the ability of one queen to attack another -> can attack on first diagonal"
+
+[ff9b7ed4-e4b6-401b-8d16-bc894d6d3dcd]
+description = "Test the ability of one queen to attack another -> can attack on second diagonal"
+
+[0a71e605-6e28-4cc2-aa47-d20a2e71037a]
+description = "Test the ability of one queen to attack another -> can attack on third diagonal"
+
+[0790b588-ae73-4f1f-a968-dd0b34f45f86]
+description = "Test the ability of one queen to attack another -> can attack on fourth diagonal"
+
+[543f8fd4-2597-4aad-8d77-cbdab63619f8]
+description = "Test the ability of one queen to attack another -> cannot attack if falling diagonals are only the same when reflected across the longest falling diagonal"

exercises/practice/queen-attack/queen-attack.ua

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+┌─╴Queen
+  # Create a new queen
+  # Queen ? Row Column
+  New ← |2 ⊙⋅(⍤ "Please implement New" 0)
+
+  # Get a queen's row
+  # Row ? Queen
+  Row ← |1 ⊙(⍤ "Please implement Row" 0)
+
+  # Get a queen's column
+  # Column ? Queen
+  Column ← |1 ⊙(⍤ "Please implement Row" 0)
+
+  # Check if two queens can attack each other
+  # Validity ? Queen1 Queen2
+  CanAttack ← |2 ⊙⋅(⍤ "Please implement CanAttack" 0)
+└─╴

exercises/practice/queen-attack/tests.ua

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+~ "queen-attack.ua" ~ Queen
+
+# Queen must have positive row
+⍤⤙≍ "invalid row" ⍣(Queen~New ¯2 2)
+
+# Queen must have row on board
+⍤⤙≍ "invalid row" ⍣(Queen~New 8 4)
+
+# Queen must have positive column
+⍤⤙≍ "invalid column" ⍣(Queen~New 2 ¯2)
+
+# Queen must have column on board
+⍤⤙≍ "invalid column" ⍣(Queen~New 4 8)
+
+# Row of queen with a valid position
+⍤⤙≍ 2 Queen~Row Queen~New 2 3
+
+# Column of queen with a valid position
+⍤⤙≍ 3 Queen~Column Queen~New 2 3
+
+# Cannot attack
+WhiteQueen ← Queen~New 2 4
+BlackQueen ← Queen~New 6 6
+⍤⤙≍ 0 Queen~CanAttack BlackQueen WhiteQueen
+
+# Can attack on same row
+WhiteQueen ← Queen~New 2 4
+BlackQueen ← Queen~New 2 6
+⍤⤙≍ 1 Queen~CanAttack BlackQueen WhiteQueen
+
+# Can attack on same column
+WhiteQueen ← Queen~New 4 5
+BlackQueen ← Queen~New 2 5
+⍤⤙≍ 1 Queen~CanAttack BlackQueen WhiteQueen
+
+# Can attack on first diagonal
+WhiteQueen ← Queen~New 2 2
+BlackQueen ← Queen~New 0 4
+⍤⤙≍ 1 Queen~CanAttack BlackQueen WhiteQueen
+
+# Can attack on second diagonal
+WhiteQueen ← Queen~New 2 2
+BlackQueen ← Queen~New 3 1
+⍤⤙≍ 1 Queen~CanAttack BlackQueen WhiteQueen
+
+# Can attack on third diagonal
+WhiteQueen ← Queen~New 2 2
+BlackQueen ← Queen~New 1 1
+⍤⤙≍ 1 Queen~CanAttack BlackQueen WhiteQueen
+
+# Can attack on fourth diagonal
+WhiteQueen ← Queen~New 1 7
+BlackQueen ← Queen~New 0 6
+⍤⤙≍ 1 Queen~CanAttack BlackQueen WhiteQueen
+
+# Cannot attack if falling diagonals are only the same when reflected across the longest falling diagonal
+WhiteQueen ← Queen~New 4 1
+BlackQueen ← Queen~New 2 5
+⍤⤙≍ 0 Queen~CanAttack BlackQueen WhiteQueen