"""
Given two strings s and t which consist of only lowercase letters.
String t is generated by random shuffling string s and then add one more letter at a random position.
Find the letter that was added in t.
"""
class Solution(object):
    def findTheDifference( self, s, t):
        """
        :type s: str
        :type t: str
        :rtype: str
        """
        for c in t:
            if s.count(c) != t.count(c):
                return c
        return ""
