摘要：
Hacker, pack your bags! time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Hacker, pack you 阅读全文
摘要：
HazelFan wants to build a rooted tree. The tree has nn nodes labeled 0 to n−1, and the father of the node labeled i is the node labeled . HazelFan won 阅读全文