Hash Maps

Question 1

What is a Load Factor?

Answer 1

Property of a hash map that determines when the hash map should be resized.

Question 2

How is load factor calculated?

Answer 2

The load factor is calculated by dividing the number of

key-value pairs in the hash map by the length of the array

Question 3

When is a hash map resized?

Answer 3

When the load factor exceeds a certain threshold.

Question 4

What is the best case big O for searching in a hash map?

Answer 4

Because hash maps use the hash code of the key to find the associated value, searches tend to be O(1).

Question 5

What is the best case big O for adding in a hash map?

Answer 5

O ( 1 )

Question 6

What is the best case big O for removing from a hash map?

Answer 6

O ( 1 )

Question 7

What is the worst case big O for removing, searching, and adding to a hash map?

Answer 7

If the keys have a limited range of hash codes, or collisions occur for other reasons, then adding, searching, and removing
from a hash map is O(n)