From atop a satellite, Nick has drawn ~N~ lines on the surface of a plane, no three of which intersect at a common point. He counts many triangles, but how many of them contain no triangles with a strictly smaller area?

Constraints

~1 \le N \le 500~

~|x_i|, |y_i| \le 2 \cdot 10^3~

All lines are pairwise distinct.

No three lines intersect at a common point.

Input Specification

The first line contains a single positive integer, ~N~.

The next ~N~ lines contain four space-separated integers, ~x_1~, ~y_1~, ~x_2~, ~y_2~, indicating a line going through distinct points ~(x_1, y_1)~ and ~(x_2, y_2)~.

Output Specification

Output the number of such triangles.

Sample Input

4
0 0 0 10
0 0 10 0
0 5 5 5
0 10 10 0

Sample Output

1