之前写过这个算法,时间长了就忘掉了,,现在不看书自己努力回想起来,对算法的理解,对线段树的理解感觉也更深了一点(可能心理作用,哈哈哈) 思路简单说一下吧 从做到右遍历每一条矩阵的边(左右边),看该边对右边的面积贡献是正还是负(矩阵左边为正,右边为负),在y轴上用线段树维护在y轴的贡献值,与x轴上该边与下一条边的差值相乘即可 // acm1.cpp: 定义控制台应用程序的入口点. // #include<iostream> #include<cstdio> #include<c…

比较水的入门题 记录矩形竖边的x坐标,离散化排序.以被标记的边建树. 扫描线段树,查询线段树内被标记的边.遇到矩形的右边就删除此边 每一段的面积是查询结果乘边的横坐标之差,求和就是答案 #include <cstdio> #include <cstring> #include <algorithm> using namespace std; ; int N,num,kase; ]; struct line{ double x,y1,y2; int flag; bool…

Atlantis Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 14378    Accepted Submission(s): 5931 Problem Description There are several ancient Greek texts that contain descriptions of the fabled i…

题目 Source http://acm.hdu.edu.cn/showproblem.php?pid=3333 Description After inventing Turing Tree, 3xian always felt boring when solving problems about intervals, because Turing Tree could easily have the solution. As well, wily 3xian made lots of new…

Stars in Your Window   Description Fleeting time does not blur my memory of you. Can it really be 4 years since I first saw you? I still remember, vividly, on the beautiful Zhuhai Campus, 4 years ago, from the moment I saw you smile, as you were walk…

分割线内容转载自http://hzwer.com/879.html --------------------------------------------------------------------------------- 第一次做线段树扫描法的题,网搜各种讲解,发现大多数都讲得太过简洁,不是太容易理解.所以自己打算写一个详细的.看完必会o(∩_∩)o 顾名思义,扫描法就是用一根想象中的线扫过所有矩形,在写代码的过程中,这根线很重要.方向的话,可以左右扫,也可以上下扫.方法是一样的,这里…

题意: 给你n个矩形,输入每个矩形的左上角坐标和右下角坐标. 然后求矩形的总面积.(矩形可能相交). 题解: 前言: 先说说做这道题的感受: 刚看到这道题顿时就懵逼了,几何 烂的渣渣.后来从网上搜题解.才知道用到线段树+离散化+扫描线.不过这是我第一次接触扫描线,根本不知道什么鬼啊.后来各种博客和论文看了一天才真正理解. 不过一想到网上的博客和论文,就来气.都什么啊,代码注释少的很而且说不明白什么意思,比如线段树怎么存每个节点的数据?为什么这么存?每个节点的数据变量都什么意思?更新的时候怎么更新…

Atlantis Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 9032    Accepted Submission(s): 3873 Problem Description There are several ancient Greek texts that contain descriptions of the fabled i…

传送门 D. R2D2 and Droid Army time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output An army of n droids is lined up in one row. Each droid is described by m integers a1, a2, ..., am, where ai is th…

题目链接:https://vjudge.net/problem/HDU-1542 There are several ancient Greek texts that contain descriptions of the fabled island Atlantis. Some of these texts even include maps of parts of the island. But unfortunately, these maps describe different reg…