When should I use a HashMap in programming?

When should I use a HashMap in programming?

You should use a HashMap when you need fast access to data via keys, especially for large datasets.

What are the advantages of using a HashMap over an Array?

HashMaps provide O(1) average time complexity for lookups, while Arrays require O(n) for searching.

Are there any downsides to using HashMaps?

Yes, HashMaps can consume more memory and may have performance issues with many collisions.

In what scenarios would an Array be better than a HashMap?

Arrays are better when you need ordered data or when the dataset is small and fixed in size.

Can you give me an example of using a HashMap in Java?

Sure! In Java, you can create a HashMap like this: HashMap<String, Integer> map = new HashMap<>(); and add elements using map.put(key, value);.