feat(content): function signatures + test cases

backend/data/questions/baseball-game.yaml

@@ -9,6 +9,28 @@ categories:
 patterns:
   - monotonic-stack
 
+function_signature: "def cal_points(operations: list[str]) -> int:"
+
+test_cases:
+  visible:
+    - input: { operations: ["5", "2", "C", "D", "+"] }
+      expected: 30
+    - input: { operations: ["5", "-2", "4", "C", "D", "9", "+", "+"] }
+      expected: 27
+    - input: { operations: ["1", "C"] }
+      expected: 0
+  hidden:
+    - input: { operations: ["1"] }
+      expected: 1
+    - input: { operations: ["5", "10", "+"] }
+      expected: 30
+    - input: { operations: ["3", "D", "D", "D"] }
+      expected: 45
+    - input: { operations: ["-5", "10", "+", "D"] }
+      expected: 20
+    - input: { operations: ["1", "2", "3", "4", "5"] }
+      expected: 15
+
 description: |
   You are keeping the scores for a baseball game with strange rules. At the beginning of the game, you start with an empty record.