The Thomas Crapper Company is hosting an office Olympics event and they want to see which employees have the best aim and accuracy when it comes to throwing an unspecified object. The main event of the office Olympics is the "Flush-tastic Throwing Challenge".
In this event, each of the $$$n$$$ employees will be asked to throw an object at a designated toilet bowl placed in the office. The company wants to know how many employees are able to successfully throw the object into the toilet bowl.
This toilet bowl is perfectly circular with center ($$$c_x$$$, $$$c_y$$$) and radius $$$r$$$. Additionally, the company has recorded that the $$$i$$$-th employee throws to the coordinate ($$$x_i$$$, $$$y_i$$$). A throw is successful if it lands within or exactly on the circular bowl.
Given the location of the employee's throws as well as the center and radius of the toilet bowl, determine the number of employees who are able to successfully throw the unspecified object into the toilet bowl.
The first line of input will contain four integers, $$$n, c_x, c_y, r$$$. Where ($$$1 \leq n \leq 10^5$$$), $$$(-10^9 \leq c_x, c_y \leq 10^9)$$$, and $$$(1 \leq r \leq 10^9)$$$.
The next $$$n$$$ lines will each contain two integers $$$x_i$$$ and $$$y_i$$$ ($$$-10^9 \leq x_i, y_i \leq 10^9$$$).
A single integer, the number of employees who are able to successfully throw the unspecified object into the toilet bowl.
4 1 2 5 0 0 -2 -2 5 6 3 3
3
