extern crate itertools;

use std::cell::RefCell;
use std::rc::Rc;
use itertools::Itertools;

struct Node {
    label: i32,
    neighbors: Vec<Rc<RefCell<Node>>>,
}
type RefNode = Rc<RefCell<Node>>;

fn make_graph() -> Vec<RefNode> {
    let mut nodes : Vec<RefNode> = vec!();
    {
        let mut make_node = |label: i32| {
            let node = Rc::new(RefCell::new(Node {
                label: label,
                neighbors: vec!()
            }));
            nodes.push(node.clone());
            node.clone()
        };

        let node1 = make_node(1);
        let node2 = make_node(2);
        let node3 = make_node(3);
        node1.borrow_mut().neighbors.push(node2.clone());
        node2.borrow_mut().neighbors.push(node1.clone());
        node2.borrow_mut().neighbors.push(node3.clone());
    }
    nodes
}

fn main () {
    let nodes = make_graph();

    for n in nodes {
        println!("node: {}", n.borrow().label);
        let neighbors: String = n.borrow()
            .neighbors
            .iter()
            .map(|n| n.borrow().label.to_string())
            .join(", ");
        println!("neighbors: {}", neighbors);
    }
}