feat(content): function signatures + test cases

backend/data/questions/average-value-of-even-numbers-divisible-by-three.yaml

@@ -9,6 +9,30 @@ categories:
 patterns:
   - prefix-sum
 
+function_signature: "def average_value(nums: list[int]) -> int:"
+
+test_cases:
+  visible:
+    - input: { nums: [1, 3, 6, 10, 12, 15] }
+      expected: 9
+    - input: { nums: [1, 2, 4, 7, 10] }
+      expected: 0
+  hidden:
+    - input: { nums: [6] }
+      expected: 6
+    - input: { nums: [6, 12, 18] }
+      expected: 12
+    - input: { nums: [1, 2, 3, 4, 5] }
+      expected: 0
+    - input: { nums: [6, 6, 6, 6] }
+      expected: 6
+    - input: { nums: [12, 24, 36, 48, 60] }
+      expected: 36
+    - input: { nums: [5, 7, 11, 13, 17, 19] }
+      expected: 0
+    - input: { nums: [6, 12, 1, 2, 3, 18] }
+      expected: 12
+
 description: |
   Given an integer array `nums` of **positive** integers, return *the average value of all even integers that are divisible by* `3`.