摘要：
"友链" Description Examples input output Solution 两两算出LCA，有两个LCA是相同的，选择另一个作为答案 这道题似乎卡常数 cpp include include include define MAXN 500005 int head[MAXN]; i 阅读全文
摘要：
"友链" Description Alice likes snow a lot! Unfortunately, this year's winter is already over, and she can't expect to have any more of it. Bob has thus 阅读全文