BOJ 9613번 GCD 합

• 문제링크 : https://www.acmicpc.net/problem/9613
• 제출링크 : https://www.acmicpc.net/source/19844531
• CPP 소스 : https://github.com/skysign/WSAPT/blob/master/BOJ/9613%EB%B2%88%20GCD%20%ED%95%A9/9613%EB%B2%88%20GCD%20%ED%95%A9.cpp