The Chef is given a list of N triangles. Each triangle is identfied by the coordinates of its three corners in the 2-D cartesian plane. His job is to figure out how many
of the given triangles are right triangles. A right triangle is a triangle in which one angle is a 90 degree angle. The vertices
of the triangles have integer coordinates and all the triangles given are valid( three points aren't colinear ).  

------ Input ------

The first line of the input contains an integer N denoting the number of triangles. Each of the following N
lines contain six space separated integers x1 y1 x2 y2 x3 y3 where (x1, y1),
(x2, y2) and (x3, y3) are the vertices of a triangle.

------ Output ------

Output one integer, the number of right triangles among the given triangles.

------ Constraints ------

$1 ≤ N ≤ 100000 (10^{5})$
$ 0 ≤ x1, y1, x2, y2, x3, y3 ≤ 20$

----- Sample Input 1 ------
5
0 5 19 5 0 0
17 19 12 16 19 0
5 14 6 13 8 7
0 4 0 14 3 14
0 2 0 14 9 2
----- Sample Output 1 ------
3
----- explanation 1 ------
The first triangle and the last two triangles of the example are right triangles.

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