Count how many characters from stones are jewels from jewels.
Example 1
Input: jewels = "z", stones = "ZZ"
Output: 0
Explanation: z is case-sensitive and does not match Z.
Output: 0
Explanation: z is case-sensitive and does not match Z.
Example 2
Input: jewels = "aA", stones = "aAAbbbb"
Output: 3
Explanation: Three of the stones are jewels.
Output: 3
Explanation: Three of the stones are jewels.