摘要：
题目链接 Problem Description As to a permutation p1,p2,⋯,pn from 1 to n, it is uncomplicated for each 1≤i≤n to calculate (li,ri) meeting the condition tha 阅读全文
摘要：
题目链接 Problem Description There is a tree with n nodes, each of which has a type of color represented by an integer, where the color of node i is ci.Th 阅读全文