LeetCode 771. Jewels and Stones

Posted on | In |
Words count in article: 167 | Reading time ≈ 1

题目

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".

Example 1:

1
2
Input: J = "aA", S = "aAAbbbb"
Output: 3

Example 2:

1
2
Input: J = "z", S = "ZZ"
Output: 0

Note:

  • S and J will consist of letters and have length at most 50.
  • The characters in J are distinct.

思路

Easy. For each stone, check if it is a jewel.

代码

1
2
3
4
5
6
7
8
class Solution(object):
    def numJewelsInStones(self, J, S):
        """
        :type J: str
        :type S: str
        :rtype: int
        """
        return sum(S.count(j) for j in J)