Question

Prefix expression can be evaluated _________

(a) from right to left

(b) from left to right

(c) from the exact middle

(d) from second right element

This question was posed to me in an interview for job.

This is a very interesting question from Trees topic in section Trees of Discrete Mathematics

Answer 1

Correct choice is (b) from left to right

The explanation is: Expressions are usually evaluated from left to right manner. Prefix expressions follow the normal rule i.e from left to right. Postfix expressions can be evaluated from right to left.