Add queen-attack exercise (#190)

Co-authored-by: Victor Goff <[email protected]>

config.json

@@ -247,6 +247,14 @@
         "prerequisites": [],
         "difficulty": 2
       },
+      {
+        "slug": "queen-attack",
+        "name": "Queen Attach",
+        "uuid": "c728a685-1b4e-4d77-9273-6ee42ca4fb0e",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "word-count",
         "name": "Word Count",

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

@@ -0,0 +1,25 @@
+# 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:
+
+```text
+  a b c d e f g h
+8 _ _ _ _ _ _ _ _ 8
+7 _ _ _ _ _ _ _ _ 7
+6 _ _ _ _ _ _ _ _ 6
+5 _ _ W _ _ _ _ _ 5
+4 _ _ _ _ _ _ _ _ 4
+3 _ _ _ _ _ _ _ _ 3
+2 _ _ _ _ _ B _ _ 2
+1 _ _ _ _ _ _ _ _ 1
+  a b c d e f g h
+```
+
+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.

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

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "BNAndras"
+  ],
+  "files": {
+    "solution": [
+      "queen_attack.vim"
+    ],
+    "test": [
+      "queen_attack.vader"
+    ],
+    "example": [
+      ".meta/example.vim"
+    ]
+  },
+  "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.vim

@@ -0,0 +1,19 @@
+function! Queen(row, column) abort
+    if a:row < 0
+        throw 'row not positive'
+    elseif a:column < 0
+        throw 'column not positive'
+    elseif a:row > 7
+        throw 'row not on board'
+    elseif a:column > 7
+        throw 'column not on board'
+    endif
+
+    return {'row': a:row, 'column': a:column, 'CanAttack': function('DoCanAttack')}
+endfunction
+
+function! DoCanAttack(other) dict
+    return self.row == a:other.row ||
+    \ self.column == a:other.column ||
+    \ (abs(a:other.column - self.column) == abs(a:other.row - self.row))
+endfunction

exercises/practice/queen-attack/.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.
+
+[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.vader

@@ -0,0 +1,82 @@
+
+Execute (queen with a valid position):
+  let g:row = 2
+  let g:column = 2
+  let g:queen = Queen(g:row, g:column)
+  AssertEqual v:t_dict, type(queen)
+
+Execute (queen must have positive row):
+  let g:row = -2
+  let g:column = 2
+  let g:expected = "row not positive"
+  AssertThrows call Queen(g:row, g:column)
+  AssertEqual g:expected, g:vader_exception
+
+Execute (queen must have row on board):
+  let g:row = 8
+  let g:column = 4
+  let g:expected = "row not on board"
+  AssertThrows call Queen(g:row, g:column)
+  AssertEqual g:expected, g:vader_exception
+
+Execute (queen must have positive column):
+  let g:row = 2
+  let g:column = -2
+  let g:expected = "column not positive"
+  AssertThrows call Queen(g:row, g:column)
+  AssertEqual g:expected, g:vader_exception
+
+Execute (queen must have column on board):
+  let g:row = 4
+  let g:column = 8
+  let g:expected = "column not on board"
+  AssertThrows call Queen(g:row, g:column)
+  AssertEqual g:expected, g:vader_exception
+
+Execute (cannot attack):
+  let g:black_queen = Queen(6, 6)
+  let g:white_queen = Queen(2, 4)
+  let g:expected = 0
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (can attack on same row):
+  let g:black_queen = Queen(2, 6)
+  let g:white_queen = Queen(2, 4)
+  let g:expected = 1
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (can attack on same column):
+  let g:black_queen = Queen(2, 5)
+  let g:white_queen = Queen(4, 5)
+  let g:expected = 1
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (can attack on first diagonal):
+  let g:black_queen = Queen(0, 4)
+  let g:white_queen = Queen(2, 2)
+  let g:expected = 1
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (can attack on second diagonal):
+  let g:black_queen = Queen(3, 1)
+  let g:white_queen = Queen(2, 2)
+  let g:expected = 1
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (can attack on third diagonal):
+  let g:black_queen = Queen(1, 1)
+  let g:white_queen = Queen(2, 2)
+  let g:expected = 1
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (can attack on fourth diagonal):
+  let g:black_queen = Queen(0, 6)
+  let g:white_queen = Queen(1, 7)
+  let g:expected = 1
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)
+
+Execute (cannot attack if falling diagonals are only the same when reflected across the longest falling diagonal):
+  let g:black_queen = Queen(2, 5)
+  let g:white_queen = Queen(4, 1)
+  let g:expected = 0
+  AssertEqual g:expected, g:black_queen.CanAttack(g:white_queen)

exercises/practice/queen-attack/queen_attack.vim

@@ -0,0 +1,3 @@
+function! Queen(row, column) abort
+  " your code goes here
+endfunction