Description

DD drew $n$ points on a two-dimensional coordinate system on a piece of paper. The coordinates of the $i$-th point are ($x_i$, $y_i$). However, she accidentally spilled ink on the paper. Assuming the ink covers a circular area with a known center and radius, how many points are covered by the ink?

Input Format

The first line contains an integer $n$.
The second line contains three integers $X$, $Y$, and $R$, representing the coordinates of the center and the radius of the circle.
The next $n$ lines each contain two integers $x_i$ and $y_i$, representing the coordinates of a point.

Output Format

Output a single line with the number of points covered by the ink.

Sample

5
1 5 8
2 5
3 5
3 4
2 3
20 20

4