BinaryTree.java

class Node {
    int value;
    Node left, right;

    public Node(int item) {
        value = item;
        left = right = null;
    }
}

class BinaryTree {
    Node root;

    // Insert a new value into the binary tree
    void insert(int value) {
        root = insertRec(root, value);
    }

    Node insertRec(Node root, int value) {
        if (root == null) {
            root = new Node(value);
            return root;
        }
        if (value < root.value) {
            root.left = insertRec(root.left, value);
        } else if (value > root.value) {
            root.right = insertRec(root.right, value);
        }
        return root;
    }

    // Search for a value in the binary tree
    boolean search(int value) {
        return searchRec(root, value);
    }

    boolean searchRec(Node root, int value) {
        if (root == null) {
            return false;
        }
        if (root.value == value) {
            return true;
        }
        // return value < root.value ? searchRec(root.left, value) : searchRec(root.right, value);
        // Maybe a little more clear.
         if (value < root.value) {
            return searchRec(root.left, value);
        } else { 
            return searchRec(root.right, value);        
        }
    }

    // In-order traversal of the binary tree
    void inOrder() {
        inOrderRec(root);
    }

    void inOrderRec(Node root) {
        if (root != null) {
            inOrderRec(root.left);
            System.out.print(root.value + " ");
            inOrderRec(root.right);
        }
    }

    public static void main(String[] args) {
        BinaryTree tree = new BinaryTree();

        // Insert values
        tree.insert(50);
        tree.insert(30);
        tree.insert(20);
        tree.insert(40);
        tree.insert(70);
        tree.insert(60);
        tree.insert(80);
        tree.insert(24);
        tree.insert(99);


        // Print in-order traversal
        System.out.println("In-order traversal:");
        tree.inOrder();

        // Search for a value
        int searchValue = 80;
        System.out.println("\nSearching for " + searchValue + ": " + (tree.search(searchValue) ? "Found" : "Not Found"));
    }
}