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Problem E
Dejavu

N points are placed in the coordinate plane.

Write a program that calculates how many ways we can choose three points so that they form a right triangle with legs parallel to the coordinate axes.

A right triangle has one 90-degree internal angle. The legs of a right triangle are its two shorter sides.

Input

The first line of input contains the integer N (3N100000), the number of points.

Each of the following N lines contains two integers X and Y (1X,Y100000), the coordinates of one point.

No pair of points will share the same pair of coordinates.

Output

Output the number of triangles.

Sample Input 1 Sample Output 1
3
4 2
2 1
1 3
0
Sample Input 2 Sample Output 2
5
1 2
2 1
2 2
2 3
3 2
4
Sample Input 3 Sample Output 3
6
10 10
20 10
10 20
20 20
30 20
30 30
8
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