pub trait Map<K: Ord, V> {
// Required methods
fn get(&self, key: &K) -> Option<V>;
fn erase(&mut self, key: &K) -> Option<V>;
fn insert(&mut self, key: K, value: V) -> Option<V>;
}
pub trait Map<K: Ord, V> {
// Required methods
fn get(&self, key: &K) -> Option<V>;
fn erase(&mut self, key: &K) -> Option<V>;
fn insert(&mut self, key: K, value: V) -> Option<V>;
}