Shmerulean
Temirulan found a piece of paper of Aidana’s favourite color “Shmerulean”. This paper looks like a convex polygon and there are stones on the borders of this paper. He wants to cut a piece of it and give to Aidana. But Aidana doesn’t like all polygons, she likes only a rhombus, from which at least it is possible to build an air snake. Help Temirulan to cut this piece of the polygon so that the remaining part is a rhombus and each of the vertices contain a stone. Help Temirulan to determine how to cut, or tell that it’s impossible.
Input
In the first line given one positive integer number n (3 ≤ n ≤ 50) - size of the polygon. In the each of the next n lines given two integers x[i], y[i] (-100 ≤ x[i], y[i] ≤ 100) - coordinates of i-th vertex. Vertices of the polygon given in clockwise order.
Output
If solution exists output 4 pair of coordinates in 4 lines in clockwise or counterclockwise order, else print -1 in single line.
