using System;

​

enum Axis {

    XPOS,

    XNEG,

    YPOS,

    YNEG

}

​

class KDPlaneNode {

    public (int x, int y) Position;

    public Axis Orientation;

    public KDPlaneNode child;

    public KDPlaneNode((int x, int y) pos, Axis orient, KDPlaneNode parent) {

        Position = pos;

        Orientation = orient;

        parent.child=this;

    }

}

​

public class KDTree {

    KDPlaneNode @base;

}

​

public class Program {

    public static void Main() {

    }

}