One old man and one old woman sit at the table and write letters.
On the table in front of them at the coordinates (xi, yi) stay N pencils. Diameter of pencils is 0 and all of them stay vertically. Man and woman decide to divide pencils into two equal groups. In order to do this old man give thread and put it on the table so that thread lay in a circle. Circle must cross over three pencils. He wants one group to get into the circle and other group not to get into the circle.
Input
At the first line of the input is one odd integer 3 ≤ N ≤ 5000.
At the next N lines are coordinates of pencils.
There are no three pencils staying in one line and there are no four pencils
staying on one circle. All coordinates are integers that are not greater than 108 by absolute value.
Output
You must output 6 integers — coordinates of three pencils over which cross thread. Inside of circle must be (N−3)/2 pencils. On the circle must be these three pencils. And outside of the circle must be others (N−3)/2 pencils. If there is no solution you must output "No solution". If there are more than one solution output any of them.
Sample
input | output |
---|
7
0 0
1 0
2 -1
2 1
1 1
0 2
-3 -1
| 0 0
1 0
2 1
|
Problem Author: Katya Ovechkina
Problem Source: Tetrahedron Team Contest May 2001