题意:给定n(<=5000)条线段,把一个矩阵分成了n+1分了,有m个玩具,放在为位置是(x,y).现在要问第几个位置上有多少个玩具. 思路:叉积,线段p1p2,记玩具为p0,那么如果(p1p2 ^ p1p0) (记得不能搞反顺序,不同的),如果他们的叉积是小于0,那么就是在线段的左边,否则右边.所以,可以用二分找,如果在mid的左边,end=mid-1 否则begin=mid+1.结束的begin,就是第一条在点右边的线段 #include <cstdio> #include <…

题目传送门:POJ 2318 TOYS Description Calculate the number of toys that land in each bin of a partitioned toy box. Mom and dad have a problem - their child John never puts his toys away when he is finished playing with them. They gave John a rectangular bo…

TOYS Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 13120   Accepted: 6334 Description Calculate the number of toys that land in each bin of a partitioned toy box. Mom and dad have a problem - their child John never puts his toys away w…

http://poj.org/problem?id=2318 TOYS Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 10178   Accepted: 4880 Description Calculate the number of toys that land in each bin of a partitioned toy box. Mom and dad have a problem - their child…

今天开始学习计算几何,百度了两篇文章,与君共勉! 计算几何入门题推荐 计算几何基础知识 题意:有一个盒子,被n块木板分成n+1个区域,每个木板从左到右出现,并且不交叉. 有m个玩具(可以看成点)放在这个盒子里,问每个区域分别有多少个玩具. 思路:首先,用叉积判断玩具是否在木板的左边,再用二分找到符合的最右边的木板,该木板答案加一. #include<stdio.h> #include<string.h> struct point{ int x,y; point(){} point(…

Toy Storage Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 5016   Accepted: 2978 Description Mom and dad have a problem: their child, Reza, never puts his toys away when he is finished playing with them. They gave Reza a rectangular box…

<题目链接> 题目大意: 给出矩形4个点和n个挡板俩顶点的位置,这n个挡板将该矩形分成 n+1块区域,再给你m个点的坐标,然你输出每个区域内有几个点. 解题思路: 用叉乘即可简单判断点与直线的位置关系,对每一个点,遍历挡板,直到找到符合的区间为止. #include <cstdio> #include <iostream> #include <algorithm> #include <cstring> using namespace std; +…

TOYS Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 8661   Accepted: 4114 Description Calculate the number of toys that land in each bin of a partitioned toy box. Mom and dad have a problem - their child John never puts his toys away wh…

题目: Description Calculate the number of toys that land in each bin of a partitioned toy box. Mom and dad have a problem - their child John never puts his toys away when he is finished playing with them. They gave John a rectangular box to put his toy…

题目大意:给出一个长方形盒子的左上点,右下点坐标.给出n个隔板的坐标,和m个玩具的坐标,求每个区间内有多少个玩具. 题目思路:利用叉积判断玩具在隔板的左方或右方,并用二分优化查找过程. #include<iostream> #include<algorithm> #include<cstring> #include<vector> #include<stdio.h> #include<stdlib.h> #include<que…