CF815D Karen and Cards 固定一维c,然后(a,b)看成坐标,矩形区域求交 1.Segment tree Beats! 2.改成不合法的区域就是求并,c反向枚举,区域只增不减且完全包含之前的 单调栈预处理找到轮廓线,然后两个指针维护顶头位置即可 #include<bits/stdc++.h> #define reg register int #define il inline #define int long long #define numb (ch^'0') using…
Description Karen just got home from the supermarket, and is getting ready to go to sleep. After taking a shower and changing into her pajamas, she looked at her shelf and saw an album. Curious, she opened it and saw a trading card collection. She re…
Petrozavodsk Summer Training Camp 2017 Day 9 Problem A. Building 题目描述:给出一棵树,在树上取出一条简单路径,使得该路径的最长上升子序列最长,问最长的长度. solution 最常见的想法就是树状dp,但空间不太够,所以选择直接计数. 每个点记住两个\(vector(f, g)\),\(f_i\)表示从叶子到\(i\)的最长的递增序列,\(g_i\)表示从叶子到\(i\)的最长的递减序列. 当算以\(i\)为根的子树的答案时,假设…