P7071 [CSP-J2020] 优秀的拆分
https://www.luogu.com.cn/problem/P7071


P7072 [CSP-J2020] 直播获奖
https://www.luogu.com.cn/problem/P7072


P7073 [CSP-J2020] 表达式
https://www.luogu.com.cn/problem/P7073


P7074 [CSP-J2020] 方格取数
https://www.luogu.com.cn/problem/P7074