# Stack Reversal using Recursion Multiple choice Questions and Answers (MCQs)

## Click on any option to know the CORRECT ANSWERS

 Question 1
Which of the following statement is true about stack?
 A Pop operation removes the top most element B Pop operation removes the bottom most element C Push operation adds new element at the bottom D Push operation removes the top most element

Question 1 Explanation:
As stack is based on LIFO(Last In First Out) principle so the deletion takes place from the topmost element. Thus pop operator removes topmost element.

 Question 2
What is the space complexity of program to reverse stack recursively?
 A O(1) B O(log n) C O(n) D O(n log n)

Question 2 Explanation:
The recursive program to reverse stack uses memory of the order n to store function call stack.

 Question 3
Stack can be reversed without using extra space by .....
 A using recursion B using linked list to implement stack C using an extra stack D it is not possible

Question 3 Explanation:
If linked list is used for implementing stack then it can be reversed without using any extra space.

 Question 4
Which of the following is considered as the top of the stack in the linked list implementation of the stack?
 A Last node B First node C Random node D Middle node

Question 4 Explanation:
First node is considered as the top element when stack is implemented using linked list.

 Question 5
What is the time complexity of the program to reverse stack when linked list is used for its implementation?
 A O(n) B O(n log n) C O(n2) D O(log n)