Problem
Everyย valid emailย consists of aย local nameย and aย domain name, separated by theย '@'
ย sign. Besides lowercase letters, the email may contain one or moreย '.'
ย orย '+'
.
- For example, inย
"alice@leetcode.com"
,ย"alice"
ย is theย local name, andย"leetcode.com"
ย is theย domain name.
If you add periodsย '.'
ย between some characters in theย local nameย part of an email address, mail sent there will be forwarded to the same address without dots in the local name. Note that this ruleย does not applyย toย domain names.
- For example,ย
"alice.z@leetcode.com"
ย andย"alicez@leetcode.com"
ย forward to the same email address.
If you add a plusย '+'
ย in theย local name, everything after the first plus signย will be ignored. This allows certain emails to be filtered. Note that this ruleย does not applyย toย domain names.
- For example,ย
"m.y+name@email.com"
ย will be forwarded toย"my@email.com"
.
It is possible to use both of these rules at the same time.
Given an array of strings where we send one email to eachย email[i]
, returnย the number of different addresses that actually receive mails.
Example 1:
Input: emails = ["test.email+alex@leetcode.com","test.e.mail+bob.cathy@leetcode.com","testemail+david@lee.tcode.com"] Output: 2 Explanation: "testemail@leetcode.com" and "testemail@lee.tcode.com" actually receive mails.
Example 2:
Input: emails = ["a@leetcode.com","b@leetcode.com","c@leetcode.com"] Output: 3
Simple Kotlin Solution
fun main(args:Array<String>){ var result = numUniqueEmails(arrayOf("test.email+alex@leetcode.com","test.email.leet+alex@code.com")) printResult("Unique Email Count ", result.toString()) } fun numUniqueEmails(emails: Array<String>): Int { var list=ArrayList<String>() for (email in emails){ var localname=email.split("@")[0].split("+")[0].replace(".","") var domain=email.split("@")[1] if(!list.contains("$localname@$domain")){ list.add("$localname@$domain") } } return list.size }