feat(content): function signatures + test cases

backend/data/questions/capitalize-the-title.yaml

@@ -8,6 +8,28 @@ categories:
 patterns:
   - two-pointers
 
+function_signature: "def capitalize_title(title: str) -> str:"
+
+test_cases:
+  visible:
+    - input: { title: "capiTalIze tHe titLe" }
+      expected: "Capitalize The Title"
+    - input: { title: "First leTTeR of EACH Word" }
+      expected: "First Letter of Each Word"
+    - input: { title: "i lOve leetcode" }
+      expected: "i Love Leetcode"
+  hidden:
+    - input: { title: "TO BE OR NOT TO BE" }
+      expected: "to be or Not to be"
+    - input: { title: "a" }
+      expected: "a"
+    - input: { title: "AB" }
+      expected: "ab"
+    - input: { title: "ABC" }
+      expected: "Abc"
+    - input: { title: "the QUICK brown FOX" }
+      expected: "The Quick Brown Fox"
+
 description: |
   You are given a string `title` consisting of one or more words separated by a single space, where each word consists of English letters. **Capitalize** the string by changing the capitalization of each word such that: