Input starts with an integer, on a line by itself, that represents the number of tracks tobe shortened. The description of each track begins with a positive integer N, on a line by itself, representing the number of recorded points that define the track. Each of the following N lines contains two integers, separated by a single space, that define the xand y-coordinates of a point on the track in metres. The points are listed in order of their appearance on the track.
Two successive points, which form a segment, will be no more than thirty metres apart and a segment will not intersect more than twenty other segments. All x- and ycoordinates have values between -10,000,000 and 10,000,000, inclusive. N has values between 1 and 100,000, inclusive.