sicily 1059. Exocenter of a Trian
来源:互联网 发布:linux 查找内容 编辑:程序博客网 时间:2024/06/10 09:45
1059. Exocenter of a Trian
Constraints
Time Limit: 1 secs, Memory Limit: 32 MB
Description
Given a triangle ABC, the Extriangles of ABC are constructed as follows:
On each side of ABC, construct a square (ABDE, BCHJ and ACFG in the figure below).
Connect adjacent square corners to form the three Extriangles (AGD, BEJ and CFH in the figure).
The Exomedians of ABC are the medians of the Extriangles, which pass through vertices of the original triangle, extended into the original triangle (LAO, MBO and NCO in the figure. As the figure indicates, the three Exomedians intersect at a common point called the Exocenter (point O in the figure).
This problem is to write a program to compute the Exocenters of triangles.
Input
The first line of the input consists of a positive integer n, which is the number of datasets that follow. Each dataset consists of 3 lines; each line contains two floating point values which represent the (two -dimensional) coordinate of one vertex of a triangle. So, there are total of (n*3) + 1 lines of input. Note: All input triangles wi ll be strongly non-degenerate in that no vertex will be within one unit of the line through the other two vertices.
Output
For each dataset you must print out the coordinates of the Exocenter of the input triangle correct to four decimal places.
Sample Input
20.0 0.09.0 12.014.0 0.03.0 4.013.0 19.02.0 -10.0
Sample Output
9.0000 3.7500-48.0400 23.3600
题目分析
找三角形的质心
具体证明可以见此
为了避免讨论斜率是否存在的问题,转化成向量运算
注意fabs(ans) < 0.0001输出0.0000
#include <stdio.h>#include <math.h>struct Point { double x, y;};struct Line { Point start, end;};int main() { int test; scanf("%d", &test); while (test--) { Point a, b, c; scanf("%lf%lf%lf%lf%lf%lf", &a.x, &a.y, &b.x, &b.y, &c.x, &c.y); Line u, v; u.start = c; u.end.x = u.start.x - a.y + b.y; u.end.y = u.start.y + a.x - b.x; v.start = b; v.end.x = v.start.x - a.y + c.y; v.end.y = v.start.y + a.x - c.x; Point inter = u.start; double t = ((u.start.x - v.start.x) * (v.start.y - v.end.y) - (u.start.y - v.start.y) * (v.start.x - v.end.x)) / ((u.start.x - u.end.x) * (v.start.y - v.end.y) - (u.start.y - u.end.y) * (v.start.x - v.end.x)); inter.x += (u.end.x - u.start.x) * t; inter.y += (u.end.y - u.start.y) * t; inter.x = fabs(inter.x) < 0.0001 ? 0.0 : inter.x; inter.y = fabs(inter.y) < 0.0001 ? 0.0 : inter.y; printf("%.4lf %.4lf\n", inter.x, inter.y); } return 0;}
- Sicily 1059. Exocenter of a Trian
- Sicily 1059. Exocenter of a Trian
- sicily 1059. Exocenter of a Trian
- Sicily.1059. Exocenter of a Trian(求垂心,向量旋转)
- 1059. Exocenter of a Trian
- 1059. Exocenter of a Trian
- Sicily 1059. Exocenter of a Triangle
- POJ1673-EXOCENTER OF A TRIANGLE
- POJ 1673 EXOCENTER OF A TRIANGLE
- pku 1673 EXOCENTER OF A TRIANGLE
- POJ 1673 EXOCENTER OF A TRIANGLE
- poj 1673 EXOCENTER OF A TRIANGLE
- POJ 1673 EXOCENTER OF A TRIANGLE
- poj 1673 EXOCENTER OF A TRIANGLE
- PKU 1673 EXOCENTER OF A TRIANGLE 三角形的垂心
- zoj 1821 || poj 1673 Exocenter of a Triangle
- poj 1673(EXOCENTER OF A TRIANGLE) (垂心证明)
- poj 1673 EXOCENTER OF A TRIANGLE(求三角形垂心)
- elasticsearch spring 集成
- CentOs安装Maven
- Android 速度检测demo
- 素数输出优化
- Hibernate 4 获取session对象的变化
- sicily 1059. Exocenter of a Trian
- 第十二周知原理第七题
- AndroidManifest详解之Application(有图更好懂)
- iOS开发面试题
- 使用AngularJS时解决的一些小问题
- 黑马程序员--Java笔记09--字符串String 及StringBuilder等及其常用方法
- 理解HTTP headers之Expires、Cache-Control、IF-Modified-Since
- Mongodb 内嵌数组操作
- AsyncTask解惑