feat(content): more test cases

backend/data/questions/subarray-sum-equals-k.yaml

@@ -9,6 +9,24 @@ categories:
 patterns:
   - prefix-sum
 
+function_signature: "def subarray_sum(nums: list[int], k: int) -> int:"
+
+test_cases:
+  visible:
+    - input: { nums: [1, 1, 1], k: 2 }
+      expected: 2
+    - input: { nums: [1, 2, 3], k: 3 }
+      expected: 2
+  hidden:
+    - input: { nums: [1], k: 1 }
+      expected: 1
+    - input: { nums: [1], k: 0 }
+      expected: 0
+    - input: { nums: [-1, -1, 1], k: 0 }
+      expected: 1
+    - input: { nums: [1, -1, 0], k: 0 }
+      expected: 3
+
 description: |
   Given an array of integers `nums` and an integer `k`, return *the total number of subarrays whose sum equals to* `k`.