https://www.peeranswer.com/question/5fb7d38187f3ed0115d0b744
https://www.onlinegdb.com/edit/HkN8DIHqP
https://paiza.io/projects/nNd8JEq7rpWQYTsQo2u_MA?language=php
https://jsfiddle.net/rjxtn91q/
https://blog.goo.ne.jp/fances26/e/f86ed4db6bd353172eeb989d9265f2a6