# Data Structure Questions and Answers-Skip List

## Data Structure Questions and Answers-Skip List

 Question 1
What is a skip list?
 A a linkedlist with size value in nodes B a linkedlist that allows faster search within an ordered sequence C a linkedlist that allows slower search within an ordered sequence D a tree which is in the form of linked list
Question 1 Explanation:
It is a datastructure, which can make search in sorted linked list faster in the same way as binary search tree and sorted array (using binary search) are faster.

 Question 2
Consider the 2-level skip list

How to access 38?

 A travel 20-30-35-38 B travel 20-30-40-38 C travel 20-38 D travel 20-40-38
Question 2 Explanation:
Let us call the nodes 20, 30, 40 as top lines and the nodes between them as normal lines. the advantage of skip lists is we can skip all the elements between the top line elements as required.

 Question 3
Skip lists are similar to which of the following datastructure?
 A stack B heap C binary search tree D balanced binary search tree
Question 3 Explanation:
As all elements lesser than the top line elements are placed infront of it and greater ones after it. please refer question for clarity. skip lists have the same asymptotic time complexities as balanced trees.

 Question 4
What is the time complexity improvement of skip lists from linked lists in insertion and deletion?
 A O(n) to O(logn) where n is number of elements B O(n) to O(1) where n is number of elements C no change D O(n) to O(n2) where n is number of elements