Find the Difference

You are given two strings s and t.

String t is generated by random shuffling string s and then add one more letter at a random position.

Return the letter that was added to t.

Example 1:

Input: s = "abcd", t = "abcde"
Output: "e"
Explanation: 'e' is the letter that was added.

Example 2:

Input: s = "", t = "y"
Output: "y"

Solution

class Solution(object):
    def findTheDifference(self, s, t):
        """
        :type s: str
        :type t: str
        :rtype: str
        """
        sum_s = [sum(ord(i) for i in s)]
        sum_t = [sum(ord(j) for j in t)]
        return chr(abs(sum_s[0] - sum_t[0]))