【leecode】宝石与石头

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

示例1

输入: J = "z", S = "ZZ"
输出: 0

示例2

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 num

if __name__ == '__main__':
    J = "Aa"
    S = "aAAbbbb"
    s = Solution()
    res = s.numJewelsInStones(J=J,S=S)
    print(res)