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 ($$$3 \leq n \le 10^5$$$, $$$n$$$ is divisible by 3).
The $$$i$$$-th of the following $$$n$$$ lines contains three integers $$$x_i$$$, $$$y_i$$$, $$$c_i$$$ ($$$|x_i|,|y_i| \leq 10^9$$$; $$$1 \leq c_i \leq 3$$$), 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.
9 2 3 1 4 1 2 2 1 3 3 4 1 5 3 2 4 4 3 2 4 1 5 2 2 3 5 3
6
3 1 1 1 2 2 2 3 3 3
3
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 $$$1, 2, 3$$$.
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