CodeForces 645D Robot Rapping Results Report
二分,拓扑排序。二分答案,然后进行拓扑排序检查,若某次发现存在两个或者两个以上入度为$0$的节点,那么不可行。#pragma comment(linker, "/STACK:1024000000,1024000000")#include<cstdio>#include<cstring>#include<cmath>#include&l...