Uttrakhand Asst. Professor Exam-39

Question

If the post order traversal of tree

gives $ab - cd * +$, then the label of the nodes A, B, C, ......, G will be

• A. a, -, b, +, c, *, d
• B. +, -, *, a, b, c, d
• C. -, a, +, b, c, d, *
• D. a, b, c, d, -, *, +

Comments

(b) is the answer

Answer 1

In post-order traversal , we've to

1. Traverse the left sub-tree of root
2. Traverse the right sub-tree of root
3. Visit the root

The nodes are visited in post-order as D  E  B  F  G  C  A

& according to the question D  E  B  F  G  C  A equals to ab - cd * +

∴ D = a , E = b , B = -  , F = c , G = d , C = * , A = +

write the things sequentially

A = + , B = -  , C = * , D = a , E = b , F = c , G = d

∴ the answer is Option B)

Answer 2

So, The answer is option B)