QUESTION:

You’re given strings J representing the types of stones that are jewels, and S representing the stones you have. Each character in Sis 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.

EXPLANATION:

这个就没有什么可说的了，就是两个循环，就可以了。

SOLUTION:

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