I. Collin-Count
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

You're still in class, zoned out, thinking about your Valentine's plan, 4 days from now. You draw many dots in your notebook and wondered: How many unordered quadruples $$$i$$$,$$$j$$$,$$$k$$$ and $$$l$$$ exist such that they form a line together.

Given $$$n$$$ points $$$P_{i}$$$ with coordinates $$$x$$$ and $$$y$$$, how many 4 points $$$P_{i}$$$, $$$P_{j}$$$, $$$P_{k}$$$ and $$$P_{l}$$$ $$$(1\leq i \lt j \lt k \lt l \leq n)$$$ are collinear ?

Input

In the first line, you're given an integer $$$n$$$, $$$(1\leq n \leq 400)$$$, the number of points you drew.

In the next $$$n$$$ lines, you're given two integers $$$x$$$ and $$$y$$$ , the x-coordinate and the y-coordinate of the $$$ith$$$ point, $$$(-10^{9}\leq x_{i},y_{i} \leq 10^{9})$$$, All points are distincts!!

Output

Print the number of possible quadruples.

Examples
Input
5
1 1
2 2
3 3
4 4
5 5
Output
5
Input
4
1 1
3 2
-9 -9
4 3
Output
0