Artist Ivanov (not the famous Ivanov who painted "Christ's apparition to people", but one of the many namesakes) once managed to rent inexpensively an excellent studio. Alas, as he soon discovered, the inexpensiveness was caused by objective reasons. A murder happened long ago in the house where he rented the room, and now the ghost living in the house each night renews blood spots on the walls of all the rooms. Ivanov's studio did not escape this damnation.
Nevertheless, being a creative person, Ivanov quickly found a simple solution to the problem. He decided to paint one or two pictures and hang them on the (single) wall where the spots appear each night so that the spots would be covered by the pictures. Of course, he does not want to spend too much time doing this work. That is why he plans to use not more than two pictures and wants the total area of the pictures to be minimal.
All the blood spots are circles. Each picture has a rectangular form with sides parallel to the axes, and the minimally possible size of a picture in each of the dimensions is 100 millimeters. If it is necessary to paint two pictures, then they should be hanged to the wall without overlaying. Each spot must be covered by exactly one picture.
The first line contains the number of the spots N, 0 < N ≤ 1000. Each of the next N lines contains the description of the corresponding spot. A spot is described by three positive integers; they are the radius of the spot and the Cartesian coordinates of the center of the spot. Everything is measured in millimeters and all these numbers do not exceed 10000.
Output the minimal total area (in square millimeters) of the pictures (not more than two) necessary to cover all the spots.
50 50 50
50 250 50
10 150 250
Problem Author: Alexander Petrov (text — Leonid Volkov)
Problem Source: Ural State University Personal Programming Contest, March 1, 2003