feat(content): function signatures + test cases

backend/data/questions/battleships-in-a-board.yaml

@@ -9,6 +9,26 @@ categories:
 patterns:
   - matrix-traversal
 
+function_signature: "def count_battleships(board: list[list[str]]) -> int:"
+
+test_cases:
+  visible:
+    - input: { board: [["X", ".", ".", "X"], [".", ".", ".", "X"], [".", ".", ".", "X"]] }
+      expected: 2
+    - input: { board: [["."]] }
+      expected: 0
+  hidden:
+    - input: { board: [["X"]] }
+      expected: 1
+    - input: { board: [["X", "X", "X"]] }
+      expected: 1
+    - input: { board: [["X"], ["X"], ["X"]] }
+      expected: 1
+    - input: { board: [["X", ".", "X"], [".", ".", "."], ["X", ".", "X"]] }
+      expected: 4
+    - input: { board: [[".", ".", "."], [".", ".", "."], [".", ".", "."]] }
+      expected: 0
+
 description: |
   Given an `m x n` matrix `board` where each cell is a battleship `'X'` or empty `'.'`, return *the number of **battleships** on the board*.