0929. Unique Email Addresses.md

Array

/**
 * @param {string[]} emails
 * @return {number}
 */
var numUniqueEmails = function(emails) {
    let set = new Set();

    emails.map((email) => {
        let [local, domain] = email.split("@");
        set.add(`${local.split("+")[0].split(".").join("")}@${domain}`);
    })

    return set.size;
};