Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

C2. Power Transmission (Hard Edition)

time limit per test

3 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputThis problem is same as the previous one, but has larger constraints.

It was a Sunday morning when the three friends Selena, Shiro and Katie decided to have a trip to the nearby power station (do not try this at home). After arriving at the power station, the cats got impressed with a large power transmission system consisting of many chimneys, electric poles, and wires. Since they are cats, they found those things gigantic.

At the entrance of the station, there is a map describing the complicated wiring system. Selena is the best at math among three friends. He decided to draw the map on the Cartesian plane. Each pole is now a point at some coordinates $$$(x_i, y_i)$$$. Since every pole is different, all of the points representing these poles are distinct. Also, every two poles are connected with each other by wires. A wire is a straight line on the plane infinite in both directions. If there are more than two poles lying on the same line, they are connected by a single common wire.

Selena thinks, that whenever two different electric wires intersect, they may interfere with each other and cause damage. So he wonders, how many pairs are intersecting? Could you help him with this problem?

Input

The first line contains a single integer $$$n$$$ ($$$2 \le n \le 1000$$$) — the number of electric poles.

Each of the following $$$n$$$ lines contains two integers $$$x_i$$$, $$$y_i$$$ ($$$-10^4 \le x_i, y_i \le 10^4$$$) — the coordinates of the poles.

It is guaranteed that all of these $$$n$$$ points are distinct.

Output

Print a single integer — the number of pairs of wires that are intersecting.

Examples

Input

4 0 0 1 1 0 3 1 2

Output

14

Input

4 0 0 0 2 0 4 2 0

Output

6

Input

3 -1 -1 1 0 3 1

Output

0

Note

In the first example:

In the second example:

Note that the three poles $$$(0, 0)$$$, $$$(0, 2)$$$ and $$$(0, 4)$$$ are connected by a single wire.

In the third example:

Codeforces (c) Copyright 2010-2019 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Nov/14/2019 23:05:19 (e1).

Desktop version, switch to mobile version.

Supported by

User lists

Name |
---|