Create tree (using preorder and postorder )

#1

Please explain the output format of this question.
o/p->
2 => 1 <= END
3 => 2 <= END
END => 3 <= END

#2

hey @samriddhi.srivastava2017, Consider the below expalnantion.
2 => 1 <= END, 1 is root here, whose left child is 2 and no right child.
3 => 2 <= END, 2 is root here, whose left child is 3 and no right child.
END => 3 <= END, 3 is root here having no children.