CF850A Five Dimensional Points
Description
You are given set of $ n $ points in 5-dimensional space. The points are labeled from $ 1 $ to $ n $ . No two points coincide.
We will call point $ a $ bad if there are different points $ b $ and $ c $ , not equal to $ a $ , from the given set such that angle between vectors  and  is acute (i.e. strictly less than ). Otherwise, the point is called good.
The angle between vectors  and  in 5-dimensional space is defined as , where  is the scalar product and  is length of .
Given the list of points, print the indices of the good points in ascending order.
Input Format
The first line of input contains a single integer $ n $ ( $ 1
Output Format
First, print a single integer $ k $ — the number of good points.
Then, print $ k $ integers, each on their own line — the indices of the good points in ascending order.
Explanation/Hint
In the first sample, the first point forms exactly a  angle with all other pairs of points, so it is good.
In the second sample, along the cd plane, we can see the points look as follows:

We can see that all angles here are acute, so no points are good.