use std::collections::BTreeMap;

fn main() {
    let mut map = BTreeMap::new();
    map.insert("key", "value");
    map.insert("key1", "value1");
    map.insert("key2", "value2");

    println!("map: {:?}", map);

    let keys = vec!["key1", "key2"]
      .into_iter()
      .filter(|key| {
          match map.get(key) {
              Some(value) => value.starts_with("value"),
              None => false
          }
      })
      .collect::<Vec<_>>();
    keys.iter().for_each(|key| {
      map.remove(key);
    });

    println!("map: {:?}", map);
}