LeetCode [771] Jewels and Stones

 771. Jewels and Stones

Easy

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.

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class Solution { public int numJewelsInStones(String J, String S) { Set<Character> set = new HashSet<>(); for(char c: J.toCharArray()) { set.add(c); } int ret = 0; for(char c:S.toCharArray()) { if(set.contains(c)) { ret++; } } return ret; } }