How does C++17 handle hashing and collision resolution?

How does C++17 handle hashing and collision resolution?

C++17 introduced several improvements in the standard library, including better support for hashing. It uses the std::unordered_map and std::unordered_set which rely on hash functions to store elements. Collision resolution is typically handled using chaining or open addressing.

Can you explain how chaining works in collision resolution?

Sure! In chaining, each bucket in the hash table contains a list (or another data structure) of all elements that hash to the same index. When a collision occurs, the new element is simply added to the list at that bucket.

What are the advantages of using open addressing instead?

Open addressing resolves collisions by finding another open slot within the hash table itself. This can lead to better cache performance and requires less memory overhead compared to chaining, but it can also lead to clustering issues.

Are there any specific hash functions recommended for C++17?

C++17 doesn't prescribe specific hash functions, but it provides std::hash as a default. You can also implement custom hash functions for your types by specializing std::hash.