feat(content): function signatures + test cases

backend/data/questions/apply-operations-to-an-array.yaml

@@ -9,6 +9,26 @@ categories:
 patterns:
   - two-pointers
 
+function_signature: "def apply_operations(nums: list[int]) -> list[int]:"
+
+test_cases:
+  visible:
+    - input: { nums: [1, 2, 2, 1, 1, 0] }
+      expected: [1, 4, 2, 0, 0, 0]
+    - input: { nums: [0, 1] }
+      expected: [1, 0]
+  hidden:
+    - input: { nums: [1, 1] }
+      expected: [2, 0]
+    - input: { nums: [2, 2, 2] }
+      expected: [4, 2, 0]
+    - input: { nums: [0, 0, 0] }
+      expected: [0, 0, 0]
+    - input: { nums: [1, 2, 3, 4] }
+      expected: [1, 2, 3, 4]
+    - input: { nums: [1, 1, 1, 1] }
+      expected: [2, 2, 0, 0]
+
 description: |
   You are given a **0-indexed** array `nums` of size `n` consisting of **non-negative** integers.