What is the time complexity of hashmaps?

What is the time complexity of hashmaps?

The average time complexity for search, insert, and delete operations in a hashmap is O(1). However, in the worst case, it can be O(n) if many elements hash to the same index.

Why does the worst-case complexity happen?

The worst-case complexity occurs due to hash collisions, where multiple keys hash to the same index, leading to a linked list or similar structure.

How can we minimize collisions in a hashmap?

To minimize collisions, you can use a good hash function that distributes keys uniformly and resize the hashmap when it reaches a certain load factor.

What is a load factor?

The load factor is a measure of how full the hashmap is, calculated as the number of entries divided by the number of buckets. A common threshold is 0.75.