Consider the label sequences obtained by the following pairs of traversals on a labeled binary tree. Which of these pairs identify a tree uniquely?
preorder and postorder
inorder and postorder
preorder and inorder
level order and postorder
To add Even if all Postorder, Preorder and Levelorder.are given tree cannot be uniquely determined.
If we know the binary tree is full then we can construct even using preorder and postorder traversal. (not given in this question)
See this https://www.geeksforgeeks.org/full-and-complete-binary-tree-from-given-preorder-and-postorder-traversals/
Following combination can uniquely identify a tree.
And following do not.
Answer: B
even if three of them (Pre, Post and Level) are given, the tree can not be constructed. Inorder is must.
http://www.cmi.ac.in/~madhavan/courses/programming06/lecture12-21sep2006.txt
option B
reference -
https://math.stackexchange.com/questions/1531727/why-is-tree-not-uniquely-possible-with-given-preorder-and-postorder-traversal
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