B'You are given n disks in the plane. The center of each disk has integer coordinates, and the radius of each disk is a positive integer. No two disks overlap in a region of positive area, but it is possible for disks to be tangent to each other. Your task is to determine whether it is possible to change the radii of the disks in such a way that: The first line contains an integer n ( 1 <= n <= 1000 ) -- the number of disks. The next n lines contain three integers each. The i -th of such lines contains x_i , y_i ( -10^9 <= q x_i, y_i <= q 10^9 ), and r_i ( 1 <= q r_i <= q 10^9 ) -- the coordinates of the center, and the radius, of the i -th disk. Print texttt{YES} if it is possible to change the radii in the desired manner. Otherwise, print texttt{NO} . In the first sample, one can decrease the radii of the first and third disk by 0.5 , and increase the radius of the second disk by 0.5 . This way, the sum of all radii decreases by 0.5 . The situation before and after changing the radii is depicted below. In the second sample, depicted below, there is no way to change the radii of the disks in the desired manner. '...