771. Jewels and Stones

Version #1 Straight forward

class Solution {
    public int numJewelsInStones(String J, String S) {
Set<Character> set = new HashSet<>();
for (int i = 0; i < J.length(); i++) {
set.add(J.charAt(i));
}
int count = 0;
for (int i = 0; i < S.length(); i++) {
if (set.contains(S.charAt(i))) count++;
}
return count;
}
}