Function dfs

841-keys-and-rooms.rs:4–13

(mmp: &mut HashSet<i32>, rooms: &Vec<Vec<i32>>, key: i32)

    use std::collections::HashSet;
    let mut mmp: HashSet<i32> = HashSet::new();
    pub fn dfs(mmp: &mut HashSet<i32>, rooms: &Vec<Vec<i32>>, key: i32) {
        let keys = rooms.get(key as usize);
        if keys == None { return }
        for key in keys.unwrap() {
            let tmp = mmp.get(key);
            if tmp.is_some() { continue }
            mmp.insert(*key);
            dfs(mmp, rooms, *key);
        }
    }
    dfs(&mut mmp, &rooms, 0);
    let mut mmp = mmp.into_iter().collect::<Vec<i32>>();
    mmp.sort();