0205-isomorphic-strings.js

var isIsomorphic = function (s, t) {
    if (s.length !== t.length) return false;

    const mapOne = new Map();
    const mapTwo = new Map();

    for (let i = 0; i < s.length; i++) {
        if (mapOne.has(s[i])) {
            if (mapOne.get(s[i]) !== t[i]) return false;
        } else mapOne.set(s[i], t[i]);

        if (mapTwo.has(t[i])) {
            if (mapTwo.get(t[i]) !== s[i]) return false;
        } else mapTwo.set(t[i], s[i]);
    }

    return true;
};