Find the Difference

Description

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:
e
Explanation:
'e' is the letter that was added.

Solution(javascript)

/**
 * @param {string} s
 * @param {string} t
 * @return {character}
 */
var findTheDifference = function(s, t) {
    s = s.split("");
    t = t.split("");
    
    for(var i = 0; i < s.length; i++){
        var index = t.indexOf(s[i]);
        t.splice(index,1);
    }
    
    return t[0];
};