771. Jewels and Stones

Easy

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".

Solution

class Solution:
    def numJewelsInStones(self, jewels: str, stones: str) -> int:
        sjewels = set(jewels)
        res = 0

        for stone in stones:
            if stone in sjewels:
                res += 1

        return res