+
+mod prelude {
+ #[cfg(feature = "hashbrown")]
+ extern crate hashbrown;
+
+ pub use alloc::{vec, vec::Vec, string::String, collections::VecDeque};
+ #[cfg(not(feature = "hashbrown"))]
+ pub use std::collections::{HashMap, HashSet, hash_map};
+ #[cfg(feature = "hashbrown")]
+ pub use self::hashbrown::{HashMap, HashSet, hash_map};
+}