第 45 届国际大学生程序设计竞赛（ICPC）亚洲网上区域赛模拟赛 B.XTL‘s Chessboard（思维）
题目链接： https://ac.nowcoder.com/acm/contest/8688/B 题目描述 Xutianli is a perfectionist, who only owns “Good Chessboard”. A well-known definition to the Good Chessboard is that there exists two integers u,v which satisfies ux+vy=1+u+v, with the given length x and width y. Once Zjx came to XTL’s home and brought a small ball. This ball was originally used to hit XTL, because he always touches fish under the pan pond every day（touch fish means dereliction of duty）. However, seeing that XTL had really worked conscientiously and enthusiastically, Zjx felt very guilty and gave the ball to XTL as a gift.