feat(content): hidden test cases

backend/data/questions/sum-of-two-integers.yaml

@@ -8,6 +8,28 @@ categories:
 patterns:
   - greedy
 
+function_signature: "def get_sum(a: int, b: int) -> int:"
+
+test_cases:
+  visible:
+    - input: { a: 1, b: 2 }
+      expected: 3
+    - input: { a: 2, b: 3 }
+      expected: 5
+  hidden:
+    - input: { a: -1, b: 1 }
+      expected: 0
+    - input: { a: 0, b: 0 }
+      expected: 0
+    - input: { a: -12, b: -8 }
+      expected: -20
+    - input: { a: 100, b: -100 }
+      expected: 0
+    - input: { a: 1000, b: -1 }
+      expected: 999
+    - input: { a: -1000, b: 1000 }
+      expected: 0
+
 description: |
   Given two integers `a` and `b`, return *the sum of the two integers without using the operators* `+` *and* `-`.