If you are given two traversal sequences, can you construct the binary tree?
Answers
It depends on what traversals are given. If one of the traversal methods is Inorder then the tree can be constructed, otherwise not.
Mirror
Therefore, following combination can uniquely identify a tree.
Inorder and Preorder.
Inorder and Postorder.
Inorder and Level-order.
And following do not.
Postorder and Preorder.
Preorder and Level-order.
Postorder and Level-order.
For example, Preorder, Level-order and Postorder traversals are same for the trees given in above diagram.
Preorder Traversal = AB
Postorder Traversal = BA
Level-Order Traversal = AB
So, even if three of them (Pre, Post and Level) are given, the tree can not be constructed.
Yes, if tranversals are provided
Explanation:
It all relies on the traversals that are provided. The tree can be created if one of the traversal techniques is Inorder; otherwise, it cannot.
Mirror
As a result, the following combination may be used to identify a tree.
There are two types of orders: in-order and pre-order.
There are two types of orders: in-order and out-of-order.
The terms "inorder" and "level-order" are used interchangeably.
And those who come after do not.
There are two types of preorders: postorder and preorder.
Pre-orders and Level-orders are both available.
The terms "postorder" and "level-order" are used interchangeably.
For the trees shown in the diagram, Preorder, Level-order, and Postorder traversals are all the same.
Traversal Traversal Traversal Traversal Traversal Traversal Traversal Travers
BA = Postorder Traversal
Traversal of Levels = AB
As a result, even if three of them are supplied (Pre, Post, and Level), the tree cannot be built.