Points#1486
On the plane, distinct points are given. Find the number of ways to choose three of them such that the area of the triangle with vertices at those points is an integer. It is assumed that even if three points lie on the same straight line, they form a triangle.
The first line contains the integer (1 \leq N \leq 10000). The following lines contain pairs of non-negative integers, defining the coordinates of the points. All coordinates do not exceed .
Output a single integer — the required number of triples of points.
Example 1