给定字符串J 代表石头中宝石的类型，和字符串 S代表你拥有的石头。 S 中每个字符代表了一种你拥有的石头的类型，你想知道你拥有的石头中有多少是宝石。

J 中的字母不重复，J 和 S中的所有字符都是字母。字母区分大小写，因此"a"和"A"是不同类型的石头。

 

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

The letters in J are guaranteed distinct, and all characters in J and S are letters. Letters are case sensitive, so "a" is considered a different type of stone from "A".

示例 1:输入: J = "aA", S = "aAAbbbb"输出: 3

输入: J = "z", S = "ZZ"输出: 0

class Solution:    def __init__(self):        pass    def numJewelsInStones(self, J, S):        """        输入: J = "aA", S = "aAAbbbb"        输出: 3        :type J: str        :type S: str        :rtype: int        """        num = 0        for j in list(J):            if j in S:                for s in list(S):                    if j == s:                        num += 1        return numif __name__ == '__main__':    J = "Aa"    S = "aAAbbbb"    s = Solution()    res = s.numJewelsInStones(J=J,S=S)    print(res)