feat(content): function signatures + test cases

backend/data/questions/can-make-arithmetic-progression-from-sequence.yaml

@@ -9,6 +9,30 @@ categories:
 patterns:
   - two-pointers
 
+function_signature: "def can_make_arithmetic_progression(arr: list[int]) -> bool:"
+
+test_cases:
+  visible:
+    - input: { arr: [3, 5, 1] }
+      expected: true
+    - input: { arr: [1, 2, 4] }
+      expected: false
+  hidden:
+    - input: { arr: [1, 2] }
+      expected: true
+    - input: { arr: [5, 5, 5, 5] }
+      expected: true
+    - input: { arr: [0, 0] }
+      expected: true
+    - input: { arr: [-1, -5, -3] }
+      expected: true
+    - input: { arr: [1, 100] }
+      expected: true
+    - input: { arr: [1, 2, 3, 4, 6] }
+      expected: false
+    - input: { arr: [10, 5, 0, -5, -10] }
+      expected: true
+
 description: |
   A sequence of numbers is called an **arithmetic progression** if the difference between any two consecutive elements is the same.