What are double and single threaded trees?

Category: QuestionsWhat are double and single threaded trees?
Editor">Editor Staff asked 1 month ago

What are double and single threaded trees?
 
(a) when both left, right nodes are having null pointers and only right node is null pointer respectively
 
(b) having 2 and 1 node
 
(c) using single and double linked lists
 
(d) using heaps and priority queues
 
Origin of the question is Threaded Binary Tree in section Binary Trees of Data Structures & Algorithms I
 
This question was posed to me in a national level competition.

1 Answers
Editor">Editor Staff answered 1 month ago

Correct choice is (a) when both left, right nodes are having null pointers and only right node is null pointer respectively
 
Explanation: They are properties of double and single threaded binary trees respectively.