摘要：
As you might remember from our previous rounds, Vova really likes computer games. Now he is playing a strategy game known as Rage of Empires. In the g 阅读全文
摘要：
归并树，划分树，主席树都能做。 https://www.bilibili.com/video/av4619406/?p=2 资源，对主席树的理解还差了一点，不是很明白它是怎么更新每个节点左儿子和右儿子编号的。 主席树：函数式线段树，步骤：① hash ② 建树 ③ 询问； （1） 建议学主席树的朋友 阅读全文