VJ组队赛->Dancing Stars on Me(5533)
来源:互联网 发布:淘宝一分钱购物在哪里 编辑:程序博客网 时间:2024/05/09 11:43
Problem Description
The sky was brushed clean by the wind and the stars were cold in a black sky. What a wonderful night. You observed that, sometimes the stars can form a regular polygon in the sky if we connect them properly. You want to record these moments by your smart camera. Of course, you cannot stay awake all night for capturing. So you decide to write a program running on the smart camera to check whether the stars can form a regular polygon and capture these moments automatically.
Formally, a regular polygon is a convex polygon whose angles are all equal and all its sides have the same length. The area of a regular polygon must be nonzero. We say the stars can form a regular polygon if they are exactly the vertices of some regular polygon. To simplify the problem, we project the sky to a two-dimensional plane here, and you just need to check whether the stars can form a regular polygon in this plane.
Formally, a regular polygon is a convex polygon whose angles are all equal and all its sides have the same length. The area of a regular polygon must be nonzero. We say the stars can form a regular polygon if they are exactly the vertices of some regular polygon. To simplify the problem, we project the sky to a two-dimensional plane here, and you just need to check whether the stars can form a regular polygon in this plane.
Input
The first line contains a integer T indicating the total number of test cases. Each test case begins with an integern , denoting the number of stars in the sky. Following n lines, each contains 2 integers xi,yi , describe the coordinates of n stars.
1≤T≤300
3≤n≤100
−10000≤xi,yi≤10000
All coordinates are distinct.
All coordinates are distinct.
Output
For each test case, please output "`YES`" if the stars can form a regular polygon. Otherwise, output "`NO`" (both without quotes).
Sample Input
330 01 11 040 00 11 01 150 00 10 22 22 0
Sample Output
NOYESNO
题目大意:给你n个点,看看这几个点能不能构成一个正n边形
题意很明确,但当时没想到怎么做啊QAQ,其实思路很简单的QAQ,找出最小的一条边len就是边长,然后判断长度等于len的条数是不是n个,即为正n边形
题意很明确,但当时没想到怎么做啊QAQ,其实思路很简单的QAQ,找出最小的一条边len就是边长,然后判断长度等于len的条数是不是n个,即为正n边形
#include <iostream>#include <algorithm>#include <cstdio>#include <cmath>using namespace std;const int N = 101;double x[N],y[N];double distance(int i,int j){return sqrt((x[i]-x[j])*(x[i]-x[j]) + (y[i]-y[j])*(y[i]-y[j]));}int main(){int t,n;cin >> t;while(t--){cin >> n;int i,j;for(i = 0; i < n; i++)scanf("%lf%lf",&x[i],&y[i]);double len = 1e9;int num = 0;for(i = 1; i < n; i++) len = min(len,distance(0,i));for(i = 0; i < n-1; i++){for(j = i+1; j < n; j++)if(distance(i,j) == len)num ++;}if(num == n)cout << "YES\n";elsecout << "NO\n";}return 0;}
阅读全文
0 0
- VJ组队赛->Dancing Stars on Me(5533)
- hdu 5533 Dancing Stars on Me(水)
- HDU 5533 Dancing Stars on Me(凸包)
- hdoj Dancing Stars on Me 5533 (数学几何&&技巧)
- HDU 5533 Dancing Stars on Me(数学+水题)
- HDU 5533 Dancing Stars on Me (凸包)
- HDU 5533 Dancing Stars on Me (暴力模拟+思维)
- hdu 5533 Dancing Stars on Me
- hdu 5533 Dancing Stars on Me
- HDU 5533 Dancing Stars on Me
- hdu 5533 Dancing Stars on Me
- 杭电5533 Dancing Stars on Me
- hdoj 5533 Dancing Stars on Me
- HDOJ 5533 Dancing Stars on Me
- 杭电-5533Dancing Stars on Me
- hdoj 5533 Dancing Stars on Me【数学】
- hdoj 5533 Dancing Stars on Me 【数学题】
- hdoj 5533 Dancing Stars on Me
- BZOJ2555 SubString 后缀自动机+LCT
- Java发送邮件换行问题
- SpringMvc后台校验实现
- HTTPClient模块的HttpGet和HttpPost--雷锋
- Gradle学习——读懂Gradle语法
- VJ组队赛->Dancing Stars on Me(5533)
- 简述PRIMARY KEY与identity(1,1)的含义
- url地址获取判断
- 韩子笑讲课资料三:各类文开篇和大纲的写法。
- 关于探探图片滑动操作
- CRUD的共公代码
- C 语言返璞归真: 指针篇(1)
- 在linux上搭建javaweb服务器
- 【N32926】简单测试ARM Linux嵌入式系Nand存储读写速度