You're given strings `jewels` representing the types of stones that are jewels, and `stones` representing the stones you have. Each character in `stones` is a type of stone you have. You want to know how many of the stones you have are also jewels.

Letters are case sensitive, so `"a "` is considered a different type of stone from `"A "`.

**Example 1:**

**Input:** jewels = "aA", stones = "aAAbbbb"
**Output:** 3

**Example 2:**

**Input:** jewels = "z", stones = "ZZ"
**Output:** 0

**Constraints:**

*   `1 <= jewels.length, stones.length <= 50`
*   `jewels` and `stones` consist of only English letters.
*   All the characters of `jewels` are **unique**.


def num_jewels_in_stones(jewels: str, stones: str) -> int:
    count = 0
    for stone in stones:
        if stone in jewels:
            count += 1
    return count
