binary-search-tree

C# & C++

using System;

public class Node
{
    public int Value { get; set; }

    public Node Left { get; set; }

    public Node Right { get; set; }

    public Node(int value, Node left, Node right)
    {
        Value = value;
        Left = left;
        Right = right;
    }
}

public class BinarySearchTree
{
    public static bool Contains(Node root, int value)
    {
        if (root == null) {
            return false;
        }

        if (root.Value == value) {
            return true;
        }

        if (value < root.Value) {
            return Contains(root.Left, value);
        } else {
            return Contains(root.Right, value);
        }
    }

    public static void Main(string[] args)
    {
        Node n1 = new Node(1, null, null);
        Node n3 = new Node(3, null, null);
        Node n2 = new Node(2, n1, n3);

        Console.WriteLine(Contains(n2, 3));
    }
}

C++ version

#include <stdexcept>
#include <string>
#include <iostream>

class Node
{
public:
    Node(int value, Node* left, Node* right)
    {
        this->value = value;
        this->left = left;
        this->right = right;
    }

    int getValue() const
    {
        return value;
    }

    Node* getLeft() const
    {
        return left;
    }

    Node* getRight() const
    {
        return right;
    }

private:
    int value;
    Node* left;
    Node* right;
};

class BinarySearchTree
{
public:
    static bool contains(const Node& root, int value)
    {
        if (&root == NULL)
        {
            return false;
        }

        if (root.getValue() == value)
        {
            return true;
        }

        if (value < root.getValue())
        {
            return contains(*root.getLeft(), value);
        }

        if (value > root.getValue())
        {
            return contains(*root.getRight(), value);
        }
    }
};

#ifndef RunTests
int main()
{
    Node n1(1, NULL, NULL);
    Node n3(3, NULL, NULL);
    Node n2(2, &n1, &n3);

    std::cout << BinarySearchTree::contains(n2, 3);
}
#endif