Similar to the C++, all of those are addressed by inserting lower-cased into the set, which can be achieved via an extra method call: set.insert(string.to_l

Similar to the C++, all of those are addressed by inserting lower-cased into the set, which can be achieved via an extra method call: set.insert(string.to_lowercase()) It also requires adjusting/deleting the type annotation on the set. https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=cc937cb3fca05c3111beda5948e93cb6 https://play.rust-lang.org/?version=stable&mode=debug&editio...