gistfile1.java

public class BinaryTree {

    private Node root;

    public void insert(int value) {
        if (root == null) {
            root = new Node(value);
        } else {
            root.insert(value);
        }
    }
}

public class Node {
  
    private int value;
    private Node left;
    private Node right;
    
    public void insert(int value) {

        if (value == this.value) {
            // we have a duplicate value, no need to store it again (since this tree is only
            // used for searching we only need to index each value once)
            return;
        }

        if (value > this.value) {
            if (right != null) {
                right.insert(value);
            } else {
                right = new Node(value);
            }
        } else {
            if (left != null) {
                left.insert(value);
            } else {
                left = new Node(value);
            }
        }
    }
}