Count Case-Sensitive Jewel Occurrences

### Problem jewels lists distinct character types that count as jewels. stones lists individual stones by character. Return how many stone occurrences have a type in jewels, treating uppercase and lowercase as different types. ```cpp class Solution { public: int numJewelsInStones(string jewels, string stones); }; ``` ### Examples **Example 1:** ```text jewels = "bC", stones = "bbCcB" Output: 3 Explanation: Two b occurrences and one C qualify. ``` **Example 2:** ```text jewels = "Q", stones = "qqQ" Output: 1 Explanation: Only the uppercase Q matches. ``` ### Constraints - Both strings have lengths from 1 through 50. - They contain English letters only. - Characters in jewels do not repeat. ### Contract considerations Preserve case sensitivity. ```hint Read the boundary condition Can each stone contribute a simple membership indicator? ``` ### Boundary reminders Preserve case sensitivity.