https://coding-prep.com/2023/02/20/zerojudge-a006-%e4%b8%80%e5%85%83%e4%ba%8c%e6%ac%a1%e6%96%b9%e7%a8%8b%e5%bc%8f/?fbclid=IwAR3cGc2eEK3sJP0auLh54Q8c-y4IqSu9rYYOE1m8CPv_2hxCgLFQEODRoBk