stonesOrJewels.js

/*
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.
*/

//Answer//

/**
 * @param {string} J
 * @param {string} S
 * @return {number}
 */
var numJewelsInStones = function(J, S) {
    let A = [];
for (let i = 0; i <J.length ; i++) {
    A.push(S.split('').filter(x=>x===J[i]).length)
}
    return A.reduce((a, b) => a + b)
};