389. Find the Difference (leetcode)

class Solution {
    public char findTheDifference(String s, String t) {
        int res = 0;
        for(int i = 0; i < s.length(); i++){
            res ^= (int) s.charAt(i);
            res ^= (int) t.charAt(i);
        }

         res ^= (int) t.charAt(s.length());

        return (char) res;
    }
}