Question

Which of the following array element will return the top-of-the-stack-element for a stack of size N elements(capacity of stack > N)?

(a) S[N-1]

(b) S[N]

(c) S[N-2]

(d) S[N+1]

The question is from Stack using Array in portion Abstract Data Types of Data Structures & Algorithms I

The question was posed to me in an online interview.

Answer 1

Correct option is (a) S[N-1]

Best explanation: Array indexing start from 0, hence N-1 is the last index.