import java.util.*;
import java.lang.*;
import java.io.*;

// Method to print the tree in pre-order traversal
void preOrderDFS(Node node) {
    if (node == null)
        return;

    // visit the parent node (parent of left & right children)
    System.out.print(node.data + " ");

    // recursively go to left subtree
    preOrderDFS(node.left);

    // recursively go to right subtree
    preOrderDFS(node.right);
}

// Method to print the tree in in-order traversal
void inOrderDFS(Node node) {
    if (node == null)
        return;

    // recursively go to left subtree
    inOrderDFS(node.left);

    // visit the parent node (parent of left & right children)
    System.out.print(node.data + " ");

    // recursively go to right subtree
    inOrderDFS(node.right);
}

// Method to print the tree in post-order traversal
void postOrderDFS(Node node) {
    if (node == null)
        return;

    // recursively go to left subtree
    postOrderDFS(node.left);

    // recursively go to right subtree
    postOrderDFS(node.right);

    // visit the parent node (parent of left & right children)
    System.out.print(node.data + " ");
}