随笔分类 - RMQ---树状数组
摘要：题意：现在给定空空的三维平面，有加点操作和询问立方体点数。 思路：考虑CDQ套CDQ。复杂度是O(NlogN*logN*logN)，可以过此题。 具体的，这是一个四维偏序问题，4维分别是(times,x,y,z)；我们知道cdq可以求出t<=T,x=X,y<=Y，在套一层就可以z<=Z了。那么一个立
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摘要：题意：询问区间有多少个连续的段，而且这段的颜色在[L,R]才算贡献，每段贡献是1。 有单点修改和区间查询。 思路：46min交了第一发树套树，T了。 稍加优化多交几次就过了。 不难想到，除了L这个点，其他的点都可以只统计这一段的段首。把位置看成x，颜色看成y，就成了二维平面就矩形内点的个数，这就是裸
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摘要：链接：https://ac.nowcoder.com/acm/contest/926/D来源：牛客网 在一维坐标系中，给定 n条有颜色的线段，第 i条线段的左右端点分别为 li和 ri,此外它的颜色为 ci。 给定m个查询，每个查询给定一个区间 [a,b]，需要求出这个区间完全包含的线段中有多
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摘要：pro：给定N+1个点的树，有M对关键点，现在让你破坏最少的点，使得M对关键点不连通。 sol：贪心，我们把M对点按照LCA深度排序，每次破坏LCA。 如果一对点(u,v,lca)，u-lca-v有点被破坏，则可以不用破坏新的点。 我们可以用dfs序+树状数组来处理。 如果破坏了一个点，则给它的子树
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摘要：Sample Input Sample Output Prof.Q is a sophisticated professor who has insights into quadrillions of sorting algorithms, especially into bubble sort.
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摘要：A permutation of size n is an array of size n such that each integer from 1 to n occurs exactly once in this array. An inversion in a permutation p is
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摘要：n players are going to play a rock-paper-scissors tournament. As you probably know, in a one-on-one match of rock-paper-scissors, two players choose t
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摘要：Vasya has decided to build a zip-line on trees of a nearby forest. He wants the line to be as long as possible but he doesn't remember exactly the hei
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摘要：题意：给定字符串char[]，以及Q个操作，操作有三种： 1：pos，chr：把pos位置的字符改为chr 2：pos：问以pos为中心的回文串长度为多长。 3：pos：问以pos，pos+1为中心的回文串长度为多长。 思路：用hash表示一段字符串或者连续子串。我们用BIT记录hash前缀和，那么
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摘要：The best programmers of Embezzland compete to develop a part of the project called "e-Government" — the system of automated statistic collecting and p
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摘要：墨墨购买了一套N支彩色画笔（其中有些颜色可能相同），摆成一排，你需要回答墨墨的提问。墨墨会像你发布如下指令： 1、 Q L R代表询问你从第L支画笔到第R支画笔中共有几种不同颜色的画笔。 2、 R P Col 把第P支画笔替换为颜色Col。为了满足墨墨的要求，你知道你需要干什么了吗？ Input 第
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摘要：DCE Coders admins are way much geekier than they actually seem! Kartik has been following that tradition lately. How? Well, he took the inversion coun
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摘要：You have N integers, A1, A2, ... , AN. You need to deal with two kinds of operations. One type of operation is to add some given number to each number
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摘要：You are given n segments on a line. There are no ends of some segments that coincide. For each segment find the number of segments it contains. Input
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摘要：Given an N*N matrix A, whose elements are either 0 or 1. A[i, j] means the number in the i-th row and j-th column. Initially we have A[i, j] = 0 (1 <=
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摘要：You have N integers, A1, A2, ... , AN. You need to deal with two kinds of operations. One type of operation is to add some given number to each number
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摘要：Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The squares fo
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摘要：You may have wondered why most extraterrestrial life forms resemble humans, differing by superficial traits such as height, colour, wrinkles, ears, ey
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摘要：Time limit per test: 1.0 seconds Memory limit: 256 megabytes Time limit per test: 1.0 seconds Memory limit: 256 megabytes Time limit per test: 1.0 sec
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摘要：题意： 给出一个矩阵，初始每个位置上的值都为0，然后有两种操作 一种是更改某个位置上的值 另一种是求某个位置附近曼哈顿距离不大于K的所有位置的值的总和 技巧： 坐标旋转，使得操作之后菱形变成方方正正的矩形，（即“曼哈顿距离”转化为“切比雪夫距离”）方便使用树状数组进行计算。 利用哈希进行离散，节约空
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