//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".

class JewelsAndStones {

public int numJewelsInStones(String J, String S) {

HashMap<Character, Integer> map = new HashMap<Character, Integer>();

for(char c: J.toCharArray()) {

map.put(c, 1);

}

int numberOfJewels = 0;

for(char c: S.toCharArray()) {

if(map.containsKey(c)) {

numberOfJewels++;

}

}

return numberOfJewels;

}

}