@[liuzhiyushishabi](/user/1121812) https://www.luogu.com.cn/problem/solution/P1919
by rnfmabj5114 @ 2023-11-17 20:11:08
洛谷不是有题解区吗？ https://www.luogu.com.cn/problem/solution/P1919
by robertuu @ 2023-11-17 20:11:12