P3046 [USACO12FEB] Symmetry G

After taking a modern art class, Farmer John has become interested in finding geometric patterns in everything around his farm. He carefully plots the locations of his N cows (2

\* Line 1: The single integer N. \* Lines 2..1+N: Line i+1 contains two space-separated integers representing the x and y coordinates of the ith cow (-10,000

\* Line 1: The number of different lines of symmetry of the point set.

The 4 cows form the corners of a square. There are 4 lines of symmetry -- one vertical, one horizontal, and two diagonal.