Driver method
public static void main ( String [ ] args ) { BinaryTree tree = new BinaryTree ( ) ; tree . root = new Node ( 1 ) ; tree . root . left = new Node ( 2 ) ; tree . root . right = new Node ( 3 ) ; tree . root . left . left = new Node ( 4 ) ; tree . root . left . right = new Node ( 5 ) ; System . out . println ( " Preorder ▁ traversal ▁ of ▁ binary ▁ tree ▁ is ▁ " ) ; tree . printPreorder ( ) ; System . out . println ( " Inorder traversal of binary tree is "); tree . printInorder ( ) ; System . out . println ( " Postorder traversal of binary tree is "); tree . printPostorder ( ) ; } }