#AT1798. F - Integer Convex Hull

F - Integer Convex Hull

F - Integer Convex Hull

Score : $600$ points

Problem Statement

We have $N$ points $P_1, P_2, \dots, P_N$ on a plane. The coordinates of $P_i$ is $(X_i, Y_i)$. We know that no three points lie on the same line.

For a subset $S$ of $\{ P_1, P_2, \dots, P_N \}$ with at least three elements, let us define the convex hull of $S$ as follows:

  • The convex hull is the convex polygon with the minimum area such that every point of $S$ is within or on the circumference of that polygon.

Find the number, modulo $(10^9 + 7)$, of subsets $S$ such that the area of the convex hull is an integer.

Constraints

  • $3 \leq N \leq 80$
  • $0 \leq |X_i|, |Y_i| \leq 10^4$
  • No three points lie on the same line.
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

NN

X1X_1 Y1Y_1

X2X_2 Y2Y_2

\vdots

XNX_N YNY_N

Output

Print the answer. Note that you are asked to find the count modulo $(10^9 + 7)$.


4
0 0
1 2
0 1
1 0
2

$ \{ P_1, P_2, P_4 \}$ and $\{ P_2, P_3, P_4 \}$ satisfy the condition.


23
-5255 7890
5823 7526
5485 -113
7302 5708
9149 2722
4904 -3918
8566 -3267
-3759 2474
-7286 -1043
-1230 1780
3377 -7044
-2596 -6003
5813 -9452
-9889 -7423
2377 1811
5351 4551
-1354 -9611
4244 1958
8864 -9889
507 -8923
6948 -5016
-6139 2769
4103 9241
4060436