C$++$

The first line in the input file contains an integer $N,$ the number of data sets to follow. Each set starts with two integers, $n$ and is the number of important places in the city that must have a subway station nearby, and $d$ is the maximum distance allowed between an important place and a subway station. Then comes $n$ lines, each line containing two integers $x$ and $)x,y(100,$ the coordinates of an important place in the capital. The central station will always have coordinates $0,0.$ All pairs of coordinates within a data set will be distinct $($and none will be $0,0).$