public class Dfs { Node root; public void DFS(Node root) { if (root == null) { return; } DFS(root.lt); DFS(root.rt); System.out.print(root.data + " "); } public static void main(String[] args) { Dfs tree = new Dfs(); tree.root = new Node(1); tree.root.lt = new Node(2); tree.root.rt = new Node(3); tree.root.lt.lt = new Node(4); tree.root.lt.rt = new Node(5); tree.root.rt.lt = new Node(6); tree.root.rt.rt = new Node(7); tree.DFS(tree.root); } public static class Node { int data; Node lt, rt; public Node(int data) { this.data = data; lt = rt = null; } } }