Java Program to Perform the Postorder Tree Traversal

// Importing all the required Packages
import java.util.*;

// Define the tree node class
class Node {
    int value;
    Node left;
    Node right;
    
    // defining the constructor
    Node(int val) {
        value = val;
        left = null;
        right = null;
    }
}

// Define the main class
class Main{
    
    // Function Definition to perform Postorder traversal
    public static void PostorderTraversal(Node node) {
        if (node == null) {
            return;
        }
        
        // Recursive calls 
        PostorderTraversal(node.left);
        PostorderTraversal(node.right);
        System.out.print(node.value + " ");
    }
    
    // Define the main function to test the Postorder traversal
    public static void main(String[] args){
        // Creating a binary tree
        Node root = new Node(1);
        root.left = new Node(2);
        root.right = new Node(3);
        root.left.left = new Node(4);
        root.left.right = new Node(5);
        
        // Perform Postorder traversal and print the output
        System.out.print("Postorder Traversal: ");
        PostorderTraversal(root);
    }
}