F.A.Q
Hand In Hand
Online Acmers
Problem Archive
Realtime Judge Status
Authors Ranklist

C/C++/Java Exams
ACM Steps
Go to Job
Contest LiveCast
ICPC@China
Best Coder beta
VIP | STD Contests
DIY | Web-DIY beta
Register new ID

# Eureka

Time Limit: 8000/4000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 4182    Accepted Submission(s): 1146

Problem Description
Professor Zhang draws $n$ points on the plane, which are conveniently labeled by $1, 2, ..., n$. The $i$-th point is at $(x_i,y_i)$. Professor Zhang wants to know the number of best sets. As the value could be very large, print it modulo $10^9+7$.

A set $P$ ($P$ contains the label of the points) is called best set if and only if there are at least one best pair in $P$. Two numbers $u$ and $v$ $(u, v \in P, u \ne v)$ are called best pair, if for every $w \in P$, $f(u,v) \ge g(u,v,w)$, where $f(u,v)=\sqrt{(x_u-x_v)^2+(y_u-y_v)^2}$ and $g(u,v,w)=\frac{f(u,v)+f(v,w)+f(w,u)}{2}$.

Input
There are multiple test cases. The first line of input contains an integer $T$, indicating the number of test cases. For each test case:

The first line contains an integer $n$ $(1 \le n \le 1000)$ -- then number of points.

Each of the following $n$ lines contains two integers $x_i$ and $y_i$ $(-10^9 \le x_i, y_i \le 10^9)$ -- coordinates of the $i$-th point.

Output
For each test case, output an integer denoting the answer.

Sample Input
3
3
1 1
1 1
1 1
3
0 0
0 1
1 0
1
0 0

Sample Output
4
3
0


Author
zimpha

Source

Statistic | Submit | Discuss | Note
 Home | Top Hangzhou Dianzi University Online Judge 3.0 Copyright © 2005-2024 HDU ACM Team. All Rights Reserved. Designer & Developer : Wang Rongtao LinLe GaoJie GanLu Total 0.000000(s) query 1, Server time : 2024-09-21 11:15:20, Gzip enabled Administration