https://www.acmicpc.net/problem/1005
https://www.acmicpc.net/problem/14438
https://www.acmicpc.net/problem/14428
https://www.acmicpc.net/problem/14427
https://www.acmicpc.net/problem/17408
https://www.acmicpc.net/problem/18436
https://www.acmicpc.net/problem/18917
https://www.acmicpc.net/problem/17082
https://www.acmicpc.net/problem/15506
https://en.cppreference.com/w/ 를 참고했습니다.