k叉树直径
样例名称：ktreed
样例5满足k=2
样例6满足特殊性质

最长回路
样例名称：maxloop
样例5满足zi<=1

华附消消乐
样例名称：xiaoxiaole

Conveyors
样例名称：conveyors
样例2满足性质A
样例4满足k=n