One of the hardest parts about being a Swift developer is that Swift's standard library is missing a bunch of key data structures. In every day app programming, it's not an issue, but in competitive programming, we end up needing to reimplement a lot of data structures that are freebies in other languages.

Swift has released a Collections module to address this, but as far as I can tell, it's not possible to import it in Leetcode.

Other languages have access to similar modules (Ruby, for example), and it would be super helpful for Swift!

Here are the docs - a bunch of stuff is still missing, but it's better than nothing!