题目链接 抄的外心模版.然后,输出认真一点.1Y. #include <cstdio> #include <cstring> #include <string> #include <cmath> #include <algorithm> using namespace std; #define eps 1e-8 struct point { double x,y; }; struct line { point a,b; }; point inte…

题目链接:http://poj.org/problem?id=1329 #include<cstdio> #include<cmath> #include<algorithm> #include<iostream> #include<cstring> using namespace std; typedef long long ll; ; int sgn(double x) { ; ? - : ; } struct Point{ double x…

Circle Through Three Points Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 4112   Accepted: 1712 Description Your team is to write a program that, given the Cartesian coordinates of three points on a plane, will find the equation of the…

题链: http://poj.org/problem?id=1329 题解: 计算几何,求过不共线的三点的圆 就是用向量暴力算出来的东西... (设出外心M的坐标,由于$|\vec{MA}|=|\vec{MB}|=|\vec{MC}|$,可以解出M点坐标.) 代码: #include<cmath> #include<cstdio> #include<cstring> #include<iostream> using namespace std; const…

题目链接:http://poj.org/problem?id=1329 输出很蛋疼,要考虑系数为0,输出也不同 #include<cstdio> #include<cstring> #include<cmath> #include<iostream> #include<algorithm> #include<queue> using namespace std; ; const double PI = acos(-1.0); cons…

The Circumference of the Circle Time Limit: 2 Seconds      Memory Limit: 65536 KB To calculate the circumference of a circle seems to be an easy task - provided you know its diameter. But what if you don't? You are given the cartesian coordinates of…

地址:http://poj.org/problem?id=1329 题目: Circle Through Three Points Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 3970   Accepted: 1667 Description Your team is to write a program that, given the Cartesian coordinates of three points on…

Circle Through Three Points Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 3169   Accepted: 1342 Description Your team is to write a program that, given the Cartesian coordinates of three points on a plane, will find the equation of the…

Circle Through Three Points Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 3766   Accepted: 1570 Description Your team is to write a program that, given the Cartesian coordinates of three points on a plane, will find the equation of the…

Circle and Points Time Limit: 5000MS   Memory Limit: 30000K Total Submissions: 8131   Accepted: 2899 Case Time Limit: 2000MS Description You are given N points in the xy-plane. You have a circle of radius one and move it on the xy-plane, so as to enc…

[题目链接] http://poj.org/problem?id=1981 [题目大意] 给出平面上一些点,问一个半径为1的圆最多可以覆盖几个点 [题解] 我们对于每个点画半径为1的圆,那么在两圆交弧上的点所画的圆,一定可以覆盖这两个点 我们对于每个点计算出其和其它点的交弧,对这些交弧计算起末位置对于圆心的极角, 对这些我们进行扫描线操作,统计最大交集数量就是答案. [代码] #include <cstdio> #include <algorithm> #include <c…

链接 套模板 不知道有没有x,y=0情况,不过这种情况都按+号输出的. #include <iostream> #include<cstdio> #include<cstring> #include<algorithm> #include<stdlib.h> #include<vector> #include<cmath> #include<queue> #include<set> using na…

Visible Lattice Points Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 7705   Accepted: 4707 Description A lattice point (x, y) in the first quadrant (x and y are integers greater than or equal to 0), other than the origin, is visible fr…

https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=2640 http://www.spoj.com/problems/SPOINTS/en/ http://poj.org/problem?id=3805 http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1298 要…

模板题,注意一下输出就可以. #include <iostream> #include <cstdio> #include <cmath> #include <algorithm> using namespace std; struct point { double x,y; }; struct triangle{ point t[3]; }t; struct Circle{ double x,y; double r; }tmp; double dist(p…

[题目链接] http://poj.org/problem?id=3090 [算法] 通过观察发现,在这个平面直角坐标系中,除了(1,1),(1,0)和(0,1),所有可见点的横纵坐标互质 那么,问题就转化为了求 2 * (phi(1) + phi(2) + ... + phi(n)) + 3 预处理phi的前缀和,O(1)回答询问,即可 [代码] #include <algorithm> #include <bitset> #include <cctype> #inc…

题目大意: 给定三角形的三点坐标 判断在其内部包含多少个整点 题解及讲解 皮克定理 多边形面积s = 其内部整点in + 其边上整点li / 2 - 1 那么求内部整点就是 in = s + 1 - li / 2 网格中两格点(整点)间经过的格点(整点)数 即边上整点 li +1=两点横向和纵向距离的最大公约数 //求线段ab之间的整点数 int lineSeg(P a,P b) { int dx=abs(a.x-b.x), dy=abs(a.y-b.y); && dy==) ; ; }…

题意:问从(0,0)到(x,y)(0≤x, y≤N)的线段没有与其他整数点相交的点数. 解法:只有 gcd(x,y)=1 时才满足条件,问 N 以前所有的合法点的和,就发现和上一题-- [poj 2478]Farey Sequence(数论--欧拉函数 找规律求前缀和) 求 x/y,gcd(x,y)=1 且 x<y 很像.   而由于这里 x可等于或大于y,于是就求 欧拉函数的前缀和*2+边缘2个点+对角线1个点. 1 #include<cstdio> 2 #include<cst…

在网上找了好久,想找一个现成的方法来用,折腾半天发现没有一个好用的,最后迫不得已自己写了一个,需要的同学可以直接拿去用, private void GetTriangleExcenterRadius(Point A, Point B, Point C, out double R, out Point center) { //same point if (A == B && A == C) { R = ; center = A; return; } double x1 = A.X, x2 =…

已知P1.P2.P3,求点O 算法:三点不在一条直线上时,通过连接任意两点,作中垂线.任意两条中垂线的交点是圆心.…

转自:http://blog.csdn.net/tyger/article/details/4480029 计算几何题的特点与做题要领:1.大部分不会很难,少部分题目思路很巧妙2.做计算几何题目,模板很重要,模板必须高度可靠.3.要注意代码的组织,因为计算几何的题目很容易上两百行代码,里面大部分是模板.如果代码一片混乱,那么会严重影响做题正确率.4.注意精度控制.5.能用整数的地方尽量用整数,要想到扩大数据的方法(扩大一倍,或扩大sqrt2).因为整数不用考虑浮点误差,而且运算比浮点快. 一.点…

//第一期 计算几何题的特点与做题要领: 1.大部分不会很难,少部分题目思路很巧妙 2.做计算几何题目,模板很重要,模板必须高度可靠. 3.要注意代码的组织,因为计算几何的题目很容易上两百行代码,里面大部分是模板.如果代码一片混乱,那么会严重影响做题正确率. 4.注意精度控制. 5.能用整数的地方尽量用整数,要想到扩大数据的方法(扩大一倍,或扩大sqrt2).因为整数不用考虑浮点误差,而且运算比浮点快. 一.点,线,面,形基本关系,点积叉积的理解 POJ 2318 TOYS(推荐) http:/…

You are to write a program to find a circle which covers a set of points and has the minimal area. There will be no more than 100 points in one problem. Input The input contains several problems. The first line of each problem is a line containing on…

Background\text{Background}Background Last night, lots of students from primary school came to our class to study OI.\text{Last night, lots of students from primary school came to our class to study OI.}Last night, lots of students from primary schoo…

Circle Through Three Points Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 20000/10000K (Java/Other) Total Submission(s) : 35   Accepted Submission(s) : 8 Problem Description Your team is to write a program that, given the Cartesian coordinat…

[题解]The Last Hole! [CF274C] 传送门:\(\text{The Last Hole!}\) \(\text{[CF274C]}\) [题目描述] 给出平面上 \(n\) 个圆的圆心坐标,最开始它们的半径都是 \(0\),然后所有圆同时开始扩大,在时刻 \(t\) 时所有圆的半径均为 \(t\) . 假设这些黑色的圆被放在一个无穷大的白色平面上,每个时刻都存在一些黑色.白色连通块.随着圆的逐渐增大,越来越多的圆会相交. 定义一个白色的封闭区域为一个"洞",求最后一…

计算几何: 堆几何模版就能够了. . .. Description Problem E 2D Geometry 110 in 1! This is a collection of 110 (in binary) 2D geometry problems. CircumscribedCircle x1 y1 x2 y2 x3 y3 Find out the circumscribed circle of triangle (x1,y1)-(x2,y2)-(x3,y3). These three p…

地址:http://poj.org/problem?id=1673 题目: EXOCENTER OF A TRIANGLE Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 3637   Accepted: 1467 Description Given a triangle ABC, the Extriangles of ABC are constructed as follows: On each side of ABC,…

一.知识目录 字符串处理 ................................................................. 3 1.KMP 算法 ............................................................ 3 2.扩展 KMP ............................................................ 6 3.Manacher 最长回文子串 .......…

参考资料 hankcs.com: POJ 1981 Circle and Points 题解 aswmtjdsj: POJ 1981 Circle and Points [定长圆覆盖最多点问题] zxy_snow: 极角排序 概念 In mathematics, the polar coordinate system is a two-dimensional coordinate system in which each point on a plane is determined by a d…