pub fn new() -> DirectedGraph<'a, T> {
        DirectedGraph {
            graph: HashMap::new(),
            v2i: HashMap::new(),
            i2v: HashMap::new(),
            id_count: 0
        }
    }
/// Constructs an empty directed graph.
Constructs an empty directed graph.
Constructs an empty directed graph .
pub fn new() -> DirectedGraph<'a, T> {
        DirectedGraph {
            graph: HashMap::new(),
            v2i: HashMap::new(),
            i2v: HashMap::new(),
            id_count: 0
        }
    }
pub fn new ( ) -> DirectedGraph < ' a , T > { DirectedGraph { graph : HashMap :: new ( ) , v2i : HashMap :: new ( ) , i2v : HashMap :: new ( ) , id_count : 0 } }
Constructs an empty directed graph.
Constructs an empty directed graph .