Leetcode 389. Find the Difference

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.

Example:

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

class Solution {public:    char findTheDifference(string s, string t) {       char result;       for(int i=0;i<t.size();++i){            string::iterator iter=find(s.begin(),s.end(),t[i]);            if(iter==s.end())                result=t[i];            else                *iter='-1';        }        return result;    }};