CF1056H Detect Robots
题目描述
有一张 $n$ 个点的图,给你 $m$ 条路径,每条路径中每个点最多出现一次,如果存在两个点 $A$、$B$,他们在两跳不同的路径中均出现,且在两条路经中 $A$ 到 $B$ 之间的点依次有一个点不同,则输出“Human”,否则输出"Robot"。
数据范围为 $3\times 10^5$。
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输入格式
每组数据第一行输入两个整数n,m;
第2~m+1行每行先给出k表示这条路径一共经过k个点,然后输入这k个点
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输出格式
Output a single line for each test case.
If the driver can be a robot, output "Robot" in a single line. Otherwise, output "Human".
You can print each letter in any case (upper or lower).
说明/提示
In the first example it is clear that the driver used two different ways to get from crossroads $ 1 $ to crossroads $ 3 $ . It must be a human.
In the second example the driver always drives the cycle $ 1 \to 2 \to 3 \to 4 \to 1 $ until he reaches destination.