std::unordered_multimap

By blending the principles of std::unordered_map and the flexibility of multiplicity, this container allows a single key to be associated with multiple values without the need to maintain a specific order.

Purpose and suitability

std::unordered_multimap is a hash-based container that permits multiple values to be associated with a single key. Unlike std::unordered_map, it doesn’t enforce unique keys. It’s especially apt in the following scenarios:

• When quick average-case lookup times are desired
• When you anticipate multiple values for the same key
• When key order doesn’t matter, as elements aren’t stored in any particular order

Choose std::unordered_multimap for situations that require non-unique keys and swift lookups. If order or unique keys matter, consider other options.

Ideal use cases

The following are some of the ideal use cases for std::unordered_multimap:

• One-to-many relationships...