using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

    }

    public static int lastPrinted = int.MinValue;

    public static bool InOrderTraversal(Node root)

    {

        if (root == null)

            return true;

        if (!InOrderTraversal(root.Left))

            return false;

        if (root.Data <= lastPrinted)

            return false;

        lastPrinted = root.Data;

        if (!InOrderTraversal(root.Right))

            return false;

        return true;

    }

    public static bool MinMax(Node root, int min = int.MinValue, int max = int.MaxValue)

    {

        if (root == null)

            return true;

        return 

            root.Data > min &&

            root.Data <= max &&

            MinMax(root.Left, min, root.Data) &&

            MinMax(root.Left.Right, root.Data, max);

    }

}

​

public class Node

{

    public Node Left { get; set; }

    public Node Right { get; set; }

    public int Data { get; set; }

}