LeetCode-Java-771. Jewels and Stones

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:Input: J = "aA", S = "aAAbbbb"
Output: 3
Example 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.

代码

class Solution {public int numJewelsInStones(String J, String S) {int lenJ = J.length();int lenS = S.length();int num=0;for(int i = 0;i<lenJ;i++){for(int j = 0;j<lenS;j++){if(J.charAt(i)-S.charAt(j)==0){num++;}}}return num;}
}