/*
* Question: 

* Given two strings s and t, determine if they are isomorphic.

* Two strings are isomorphic if the characters in s can be replaced to get t.

* All occurrences of a character must be replaced with another character while preserving the order of characters. No two characters may map to the same character but a character may map to itself.

*For example,
*Given "egg", "add", return true.

*Given "foo", "bar", return false.

*Given "paper", "title", return true.

*Note:
* You may assume both s and t have the same length.
*/

// 128ms
/**
 * @param {string} s
 * @param {string} t
 * @return {boolean}
 */
var isIsomorphic = function(s, t) {
    
    var i = s.length - 1;
    var sMap = {};
    var tMap = {};
   
    for (; 0