feat(content): hidden test cases

backend/data/questions/check-if-array-pairs-are-divisible-by-k.yaml

@@ -10,6 +10,30 @@ categories:
 patterns:
   - prefix-sum
 
+function_signature: "def can_arrange(arr: list[int], k: int) -> bool:"
+
+test_cases:
+  visible:
+    - input: { arr: [1, 2, 3, 4, 5, 10, 6, 7, 8, 9], k: 5 }
+      expected: true
+    - input: { arr: [1, 2, 3, 4, 5, 6], k: 7 }
+      expected: true
+    - input: { arr: [1, 2, 3, 4, 5, 6], k: 10 }
+      expected: false
+  hidden:
+    - input: { arr: [-1, 1, -2, 2, -3, 3], k: 3 }
+      expected: true
+    - input: { arr: [0, 0, 0, 0], k: 5 }
+      expected: true
+    - input: { arr: [5, 5], k: 5 }
+      expected: true
+    - input: { arr: [1, 2], k: 4 }
+      expected: false
+    - input: { arr: [-10, 10], k: 2 }
+      expected: true
+    - input: { arr: [3, 3, 3, 3, 3, 3], k: 3 }
+      expected: true
+
 description: |
   Given an array of integers `arr` of even length `n` and an integer `k`.