How does hashing work in C++11 unordered_set?

Can you explain how hashing works in C++11's unordered_set?

Sure! In C++11, an unordered_set uses a hash table to store its elements, allowing for average constant time complexity for insertions, deletions, and lookups.

What is the role of the hash function in unordered_set?

The hash function computes an index for each element, which determines where the element is stored in the hash table. This helps in quickly locating elements.

Can I use custom types in unordered_set?

Yes, you can use custom types in unordered_set, but you need to provide a hash function and an equality function for those types.

What happens if two elements have the same hash value?

If two elements have the same hash value, they will be stored in the same bucket, and the unordered_set will handle this collision using a method like chaining.

Are there any performance considerations I should be aware of?

Yes, the performance can degrade if the hash function is not well-distributed, leading to many collisions. It's important to choose a good hash function.