pub fn add_edge(&mut self, u: usize, v: usize) {
        self.next.push(self.first[u]);
        self.first[u] = Some(self.num_e());
        self.endp.push(v);
    }
/// Adds a directed edge from u to v.
Adds a directed edge from u to v.
Adds a directed edge from u to v .
pub fn add_edge(&mut self, u: usize, v: usize) {
        self.next.push(self.first[u]);
        self.first[u] = Some(self.num_e());
        self.endp.push(v);
    }
pub fn add_edge ( & mut self , u : usize , v : usize ) { self . next . push ( self . first [ u ] ) ; self . first [ u ] = Some ( self . num_e ( ) ) ; self . endp . push ( v ) ; }
Adds a directed edge from u to v.
Adds a directed edge from u to v .
&mut self
u
usize
v
usize
&mut self
u
usize
v
usize