B"On an endless checkered sheet of paper, n cells are chosen and colored in three colors, where n is divisible by 3 . It turns out that there are exactly frac{n}{3} marked cells of each of three colors! Find the largest such k that it's possible to choose frac{k}{3} cells of each color, remove all other marked cells, and then select three rectangles with sides parallel to the grid lines so that the following conditions hold: The first line of the input contains a single integer n -- the number of the marked cells ( 3 <= q n <= 10^5 , n is divisible by 3). The i -th of the following n lines contains three integers x_i , y_i , c_i ( |x_i|,|y_i| <= q 10^9 ; 1 <= q c_i <= q 3 ), where (x_i, y_i) are the coordinates of the i -th marked cell and c_i is its color. It's guaranteed that all cells (x_i, y_i) in the input are distinct, and that there are exactly frac{n}{3} cells of each color. Output a single integer k -- the largest number of cells you can leave. In the first sample, it's possible to leave 6 cells with indexes 1, 5, 6, 7, 8, 9 . In the second sample, it's possible to leave 3 cells with indexes 1, 2, 3 . "...