Refactor graph and misc

This commit is contained in:
hal8174 2025-03-02 22:51:25 +01:00
parent 5f5fe0c149
commit 8f163269bd
22 changed files with 126 additions and 45 deletions

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[package]
name = "factorio-graph"
version = "0.1.0"
edition = "2024"
[dependencies]
tracing = "0.1.41"

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pub mod priority_queue;
pub mod wheighted_graph;

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use std::{collections::HashMap, fmt::Debug};
use super::PriorityQueue;
#[derive(Debug)]
pub struct BinaryHeap<Item> {
nextfree: usize,
data: Vec<BinaryHeapEntry<Item>>,
}
#[derive(Debug)]
struct BinaryHeapEntry<Item> {
id: usize,
item: Item,
}
impl<Item> BinaryHeap<Item>
where
Item: PartialOrd,
{
fn downheap(&mut self, index: usize) {
let left = 2 * index + 1;
let right = 2 * index + 2;
if right < self.data.len() {
let smaller = if self.data[left].item < self.data[right].item {
left
} else {
right
};
if self.data[index].item > self.data[smaller].item {
self.data.swap(index, smaller);
self.downheap(smaller);
}
} else if left < self.data.len() && self.data[index].item > self.data[left].item {
self.data.swap(index, left);
self.downheap(left);
}
}
fn upheap(&mut self, index: usize) {
if index > 0 {
let parent = (index - 1) / 2;
if self.data[parent].item > self.data[index].item {
self.data.swap(parent, index);
self.upheap(parent);
}
}
}
fn search(&self, id: usize) -> Option<usize> {
for (i, d) in self.data.iter().enumerate() {
if d.id == id {
return Some(i);
}
}
None
}
}
impl<Item> PriorityQueue<Item> for BinaryHeap<Item>
where
Item: PartialOrd + Clone,
{
type Handle = usize;
fn insert(&mut self, item: Item) -> Self::Handle {
self.data.push(BinaryHeapEntry {
id: self.nextfree,
item: item.clone(),
});
self.upheap(self.data.len() - 1);
self.nextfree += 1;
self.nextfree - 1
}
fn pop_min(&mut self) -> Option<Item> {
if self.data.is_empty() {
None
} else {
let d = self.data.swap_remove(0);
self.downheap(0);
Some(d.item)
}
}
fn decrease_key(&mut self, handle: &Self::Handle, f: impl Fn(&mut Item)) {
if let Some(index) = self.search(*handle) {
f(&mut self.data[index].item);
self.upheap(index);
}
}
fn new() -> Self {
Self {
data: Vec::new(),
nextfree: 0,
}
}
}
#[derive(Debug)]
pub struct Trace<P> {
inner: P,
}
impl<P, I> PriorityQueue<I> for Trace<P>
where
I: PartialOrd + Clone + Debug,
P: PriorityQueue<I>,
{
type Handle = P::Handle;
fn new() -> Self {
println!("New priority queue.");
Self { inner: P::new() }
}
fn insert(&mut self, item: I) -> Self::Handle {
println!("Insert: {item:?}");
self.inner.insert(item)
}
fn pop_min(&mut self) -> Option<I> {
let min = self.inner.pop_min();
println!("Pop min: {min:?}");
min
}
fn decrease_key(&mut self, handle: &Self::Handle, f: impl Fn(&mut I)) {
self.inner.decrease_key(handle, |i| {
let old_i = i.clone();
f(i);
println!("Decrease key: {old_i:?} -> {i:?}");
})
}
}
#[derive(Debug)]
pub struct FastBinaryHeap<Item> {
nextfree: usize,
data: Vec<BinaryHeapEntry<Item>>,
map: HashMap<usize, usize>,
}
impl<Item> FastBinaryHeap<Item>
where
Item: PartialOrd,
{
fn downheap(&mut self, index: usize) {
let left = 2 * index + 1;
let right = 2 * index + 2;
if right < self.data.len() {
let smaller = if self.data[left].item < self.data[right].item {
left
} else {
right
};
if self.data[index].item > self.data[smaller].item {
self.data.swap(index, smaller);
self.downheap(smaller);
}
} else if left < self.data.len() && self.data[index].item > self.data[left].item {
self.data.swap(index, left);
self.downheap(left);
}
self.map.insert(self.data[index].id, index);
}
fn upheap(&mut self, index: usize) {
if index > 0 {
let parent = (index - 1) / 2;
if self.data[parent].item > self.data[index].item {
self.data.swap(parent, index);
self.upheap(parent);
}
}
self.map.insert(self.data[index].id, index);
}
fn search(&self, id: usize) -> Option<usize> {
self.map.get(&id).copied()
}
}
impl<Item> PriorityQueue<Item> for FastBinaryHeap<Item>
where
Item: PartialOrd + Clone,
{
type Handle = usize;
fn insert(&mut self, item: Item) -> Self::Handle {
self.map.insert(self.nextfree, self.data.len());
self.data.push(BinaryHeapEntry {
id: self.nextfree,
item: item.clone(),
});
self.upheap(self.data.len() - 1);
self.nextfree += 1;
self.nextfree - 1
}
fn pop_min(&mut self) -> Option<Item> {
if self.data.is_empty() {
None
} else {
let d = self.data.swap_remove(0);
self.map.remove(&d.id);
if !self.data.is_empty() {
self.downheap(0);
}
Some(d.item)
}
}
fn decrease_key(&mut self, handle: &Self::Handle, f: impl Fn(&mut Item)) {
if let Some(index) = self.search(*handle) {
f(&mut self.data[index].item);
self.upheap(index);
}
}
fn new() -> Self {
Self {
data: Vec::new(),
map: HashMap::new(),
nextfree: 0,
}
}
}

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use std::fmt::Debug;
use super::PriorityQueue;
type Index = u32;
pub struct FibonacciHeap<I> {
min: Option<Index>,
data: Vec<Option<Node<I>>>,
free: Vec<Index>,
temp: [Option<Index>; 64],
}
impl<I: std::fmt::Debug> std::fmt::Debug for FibonacciHeap<I> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
struct PrintData<'a, I>(&'a Vec<Option<Node<I>>>);
impl<I: Debug> Debug for PrintData<'_, I> {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_map()
.entries(self.0.iter().enumerate().filter_map(|d| {
if let (i, Some(c)) = d {
Some((i, c))
} else {
None
}
}))
.finish()
}
}
f.debug_struct("FibonacciHeap")
.field("min", &self.min)
.field("data", &PrintData(&self.data))
.field("free", &self.free)
.finish()
}
}
#[derive(Debug)]
pub struct FibonacciHeapHandle(Index);
#[derive(Debug)]
struct Node<I> {
item: I,
parent: Index,
left: Index,
right: Index,
child: Index,
mark: bool,
rank: u16,
}
impl<I> Node<I> {
fn new(item: I) -> Self {
Self {
item,
parent: 0,
left: 0,
right: 0,
child: 0,
mark: false,
rank: 0,
}
}
}
impl<I> FibonacciHeap<I>
where
I: PartialOrd,
{
fn add_to_list(&mut self, list: Index, i: Index) {
let right = self.get(list).right;
let n = self.get_mut(i);
n.right = right;
n.left = list;
self.get_mut(right).left = i;
self.get_mut(list).right = i;
}
fn remove_from_list(&mut self, i: Index) -> Option<Index> {
let left = self.get(i).left;
if left == i {
return None;
}
let right = self.get(i).right;
self.get_mut(left).right = right;
self.get_mut(right).left = left;
Some(right)
}
fn insert_tree(&mut self, i: Index) {
if let Some(min) = self.min {
self.add_to_list(min, i);
self.get_mut(i).parent = i;
if self.get(i).item < self.get(min).item {
self.min = Some(i);
}
} else {
let m = self.get_mut(i);
m.parent = i;
m.left = i;
m.right = i;
self.min = Some(i);
}
}
fn union(&mut self, a: Index, b: Index) -> Index {
let min;
let max;
if self.get(a).item < self.get(b).item {
min = a;
max = b;
} else {
min = b;
max = a;
}
if self.get(min).rank == 0 {
self.get_mut(min).child = max;
self.get_mut(min).rank = 1;
let m = self.get_mut(max);
m.parent = min;
m.left = max;
m.right = max;
} else {
self.get_mut(max).parent = min;
self.add_to_list(self.get(min).child, max);
self.get_mut(min).rank += 1;
}
min
}
fn insert_temp(&mut self, i: Index) {
let rank = self.get(i).rank;
if let Some(t) = self.temp[rank as usize].take() {
let m = self.union(t, i);
self.insert_temp(m);
} else {
self.temp[rank as usize] = Some(i);
}
}
fn insert_data(&mut self, data: I) -> Index {
if let Some(i) = self.free.pop() {
self.data[i as usize] = Some(Node::new(data));
i
} else {
let i = self.data.len() as Index;
self.data.push(Some(Node::new(data)));
i
}
}
fn get(&self, i: Index) -> &Node<I> {
self.data.get(i as usize).unwrap().as_ref().unwrap()
}
fn get_mut(&mut self, i: Index) -> &mut Node<I> {
self.data.get_mut(i as usize).unwrap().as_mut().unwrap()
}
fn remove_data(&mut self, i: Index) -> I {
let n = self.data[i as usize].take().unwrap();
self.free.push(i);
n.item
}
fn cut(&mut self, i: Index) {
if self.get(i).item < self.get(self.min.unwrap()).item {
self.min = Some(i);
}
let parent = self.get(i).parent;
if parent == i {
return;
}
let c = self.remove_from_list(i);
if self.get(parent).rank > 1 {
self.get_mut(parent).child = c.unwrap();
}
self.get_mut(parent).rank -= 1;
self.add_to_list(self.min.unwrap(), i);
self.get_mut(i).mark = false;
self.get_mut(i).parent = i;
if self.get(parent).mark {
self.cut(parent);
} else {
self.get_mut(parent).mark = true;
}
}
}
impl<I> PriorityQueue<I> for FibonacciHeap<I>
where
I: PartialOrd,
{
type Handle = FibonacciHeapHandle;
fn new() -> Self {
FibonacciHeap {
min: None,
data: Vec::new(),
free: Vec::new(),
temp: [None; 64],
}
}
fn insert(&mut self, item: I) -> Self::Handle {
let i = self.insert_data(item);
self.insert_tree(i);
FibonacciHeapHandle(i)
}
fn pop_min(&mut self) -> Option<I> {
if let Some(min) = self.min.take() {
if self.get(min).rank != 0 {
let mut c = self.get(min).child;
loop {
let t = c;
c = self.get(c).right;
self.add_to_list(min, t);
self.get_mut(t).parent = t;
self.get_mut(t).mark = false;
if c == self.get(min).child {
break;
}
}
}
if let Some(m) = self.remove_from_list(min) {
let mut c = m;
loop {
let t = c;
c = self.get(c).right;
self.insert_temp(t);
if c == m {
break;
}
}
for i in 0..self.temp.len() {
if let Some(i) = self.temp[i].take() {
if let Some(min) = self.min {
self.add_to_list(min, i);
if self.get(i).item < self.get(min).item {
self.min = Some(i);
}
} else {
self.get_mut(i).left = i;
self.get_mut(i).right = i;
self.min = Some(i);
}
}
}
}
Some(self.remove_data(min))
} else {
None
}
}
fn decrease_key(&mut self, handle: &Self::Handle, f: impl Fn(&mut I)) {
let h = self.get_mut(handle.0);
f(&mut h.item);
self.cut(handle.0);
}
}

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pub mod binary_heap;
pub mod fibonacci_heap;
pub trait PriorityQueue<Item>
where
Item: PartialOrd,
{
type Handle;
fn new() -> Self;
// fn with_capacity() -> Self {
// Self::new()
// }
fn insert(&mut self, item: Item) -> Self::Handle;
fn pop_min(&mut self) -> Option<Item>;
fn decrease_key(&mut self, handle: &Self::Handle, f: impl Fn(&mut Item));
}
#[cfg(test)]
mod tests {
use super::binary_heap::{BinaryHeap, FastBinaryHeap};
use super::fibonacci_heap::FibonacciHeap;
use super::PriorityQueue;
macro_rules! test_generics {
($($fun_mul:ident )+ ; $gen:ident $($gen_mul:ident)+) => {
test_generics!(@internal_mod $($fun_mul )*; $gen);
test_generics!($($fun_mul )*; $($gen_mul )*);
};
($($fun_mul:ident )+ ;$gen:ident) => {
test_generics!(@internal_mod $($fun_mul )*; $gen);
};
(@internal_mod $($fun_mul:ident )+; $gen:ident) => {
#[allow(non_snake_case)]
mod $gen {
test_generics!(@internal $($fun_mul )*; $gen);
}
};
(@internal $fun:ident $($fun_mul:ident )+; $gen:ident) => {
test_generics!(@internal $fun; $gen);
test_generics!(@internal $($fun_mul )*; $gen);
};
(@internal $fun:ident; $gen:ident) => {
#[test]
fn $fun() {
super::super::$fun::<super::super::$gen<usize>>();
}
}
}
mod test_macro {
test_generics!(basic_generic decrease_key_generic; BinaryHeap FastBinaryHeap FibonacciHeap);
}
fn basic_generic<T: PriorityQueue<usize>>() {
let mut q = T::new();
q.insert(2);
q.insert(3);
q.insert(10);
q.insert(12);
q.insert(9);
q.insert(6);
q.insert(4);
q.insert(5);
q.insert(8);
q.insert(7);
q.insert(11);
q.insert(1);
assert_eq!(q.pop_min(), Some(1));
assert_eq!(q.pop_min(), Some(2));
assert_eq!(q.pop_min(), Some(3));
assert_eq!(q.pop_min(), Some(4));
assert_eq!(q.pop_min(), Some(5));
assert_eq!(q.pop_min(), Some(6));
assert_eq!(q.pop_min(), Some(7));
assert_eq!(q.pop_min(), Some(8));
assert_eq!(q.pop_min(), Some(9));
assert_eq!(q.pop_min(), Some(10));
assert_eq!(q.pop_min(), Some(11));
assert_eq!(q.pop_min(), Some(12));
assert_eq!(q.pop_min(), None);
}
fn decrease_key_generic<T: PriorityQueue<usize>>() {
let mut q = T::new();
q.insert(4);
let h = q.insert(5);
q.decrease_key(&h, |i| *i -= 3);
assert_eq!(q.pop_min(), Some(2));
assert_eq!(q.pop_min(), Some(4));
}
}

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use super::WheightedGraph;
pub struct WheightedAdjacencyList {
pub(crate) nodes: Vec<usize>,
pub(crate) edges: Vec<(usize, f64)>,
}
impl WheightedGraph for WheightedAdjacencyList {
type Node = usize;
fn num_edges(&self, node: &Self::Node) -> usize {
assert!(*node < self.nodes.len());
if *node == self.nodes.len() - 1 {
self.nodes.len() - self.nodes[0]
} else {
self.nodes[node + 1] - self.nodes[*node]
}
}
fn edge(&self, node: &Self::Node, num: usize) -> Option<(Self::Node, f64)> {
if num < self.num_edges(node) {
Some(self.edges[self.nodes[*node] + num])
} else {
None
}
}
}

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pub mod adjacency_list;
pub mod shortest_path;
pub mod steiner_tree;
pub trait WheightedGraph: Sized {
type Node;
fn num_edges(&self, node: &Self::Node) -> usize {
self.edge_iter(node).count()
}
fn edge(&self, node: &Self::Node, num: usize) -> Option<(Self::Node, f64)>;
fn edge_iter<'a, 'b>(&'a self, node: &'b Self::Node) -> WheightedGraphEdgeIter<'a, 'b, Self> {
WheightedGraphEdgeIter::new(self, node)
}
}
pub struct WheightedGraphEdgeIter<'a, 'b, G>
where
G: WheightedGraph,
{
graph: &'a G,
node: &'b G::Node,
count: usize,
}
impl<'a, 'b, G> WheightedGraphEdgeIter<'a, 'b, G>
where
G: WheightedGraph,
{
pub fn new(graph: &'a G, node: &'b G::Node) -> Self {
Self {
graph,
node,
count: 0,
}
}
}
impl<G> Iterator for WheightedGraphEdgeIter<'_, '_, G>
where
G: WheightedGraph,
{
type Item = (G::Node, f64);
fn next(&mut self) -> Option<Self::Item> {
self.count += 1;
self.graph.edge(self.node, self.count - 1)
}
}

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use std::{collections::HashMap, fmt::Debug, hash::Hash, hash::Hasher};
use tracing::{field::Empty, trace_span};
use crate::priority_queue::PriorityQueue;
use super::WheightedGraph;
#[derive(Debug, Clone, Copy)]
pub struct QueueObject<N> {
node: N,
score: f64,
}
impl<N> QueueObject<N> {
fn new(node: N, score: f64) -> Self {
Self { node, score }
}
}
impl<N> PartialOrd for QueueObject<N> {
fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
self.score.partial_cmp(&other.score)
}
}
impl<N> PartialEq for QueueObject<N> {
fn eq(&self, other: &Self) -> bool {
self.score == other.score
}
}
impl<N> Hash for QueueObject<N>
where
N: Hash,
{
fn hash<H: Hasher>(&self, state: &mut H) {
self.node.hash(state);
}
}
#[derive(Debug)]
struct MapObject<N, H> {
parent: N,
score: f64,
key: Option<H>,
}
impl<N, H> MapObject<N, H> {
fn new(parent: N, score: f64, key: H) -> Self {
Self {
parent,
score,
key: Some(key),
}
}
}
pub fn dijkstra<G, P, E>(graph: &G, start: G::Node, end: E) -> Option<Vec<G::Node>>
where
P: PriorityQueue<QueueObject<G::Node>> + Debug,
P::Handle: Debug,
G::Node: Eq + Hash + Clone + Debug,
G: WheightedGraph,
E: Fn(&'_ G::Node) -> bool,
{
let span = trace_span!("graph", seen_nodes = Empty, visited_nodes = Empty).entered();
if end(&start) {
return Some(vec![start]);
}
let mut map: HashMap<G::Node, MapObject<G::Node, P::Handle>> = HashMap::new();
let mut q = P::new();
q.insert(QueueObject::new(start.clone(), 0.0));
let mut visited_nodes: usize = 1;
let mut end_node = None;
while let Some(o) = q.pop_min() {
visited_nodes += 1;
if let Some(m) = map.get_mut(&o.node) {
m.key = None;
}
if end(&o.node) {
end_node = Some(o.node);
break;
}
for (node, wheight) in graph.edge_iter(&o.node) {
let score = o.score + wheight;
if let Some(n) = map.get_mut(&node) {
if let Some(h) = &n.key {
if score < n.score {
n.parent = o.node.clone();
n.score = score;
q.decrease_key(h, |i| i.score = score);
}
}
} else {
let h = q.insert(QueueObject::new(node.clone(), o.score + wheight));
map.insert(node, MapObject::new(o.node.clone(), o.score + wheight, h));
}
}
// dbg!(&q);
}
span.record("seen_nodes", map.len());
span.record("visited_nodes", visited_nodes);
if let Some(end_node) = end_node {
map.get(&end_node)?;
let mut result = vec![end_node];
// dbg!(&map);
loop {
let parent = map.get(result.last().expect("last")).expect("get");
result.push(parent.parent.clone());
if parent.parent == start {
break;
}
}
result.reverse();
Some(result)
} else {
None
}
}
struct GraphWrapper<'a, G, F> {
g: &'a G,
f: F,
}
impl<G: WheightedGraph, F: Fn(&G::Node) -> f64> WheightedGraph for GraphWrapper<'_, G, F> {
type Node = G::Node;
fn edge(&self, node: &Self::Node, num: usize) -> Option<(Self::Node, f64)> {
self.g.edge(node, num).map(|(n, s)| {
let s = s - (self.f)(node) + (self.f)(&n);
(n, s)
})
}
}
pub fn a_star<G, P, E, F>(graph: &G, start: G::Node, end: E, dist: F) -> Option<Vec<G::Node>>
where
P: PriorityQueue<QueueObject<G::Node>> + Debug,
P::Handle: Debug,
G::Node: Eq + Hash + Clone + Debug,
G: WheightedGraph,
E: Fn(&'_ G::Node) -> bool,
F: Fn(&G::Node) -> f64,
{
let g = GraphWrapper { g: graph, f: dist };
dijkstra::<GraphWrapper<G, F>, P, E>(&g, start, end)
}
#[cfg(test)]
mod test {
use crate::{
priority_queue::{binary_heap::BinaryHeap, fibonacci_heap::FibonacciHeap},
wheighted_graph::{
WheightedGraph, adjacency_list::WheightedAdjacencyList, shortest_path::dijkstra,
},
};
#[test]
fn trivial() {
let a = WheightedAdjacencyList {
nodes: vec![0, 1],
edges: vec![(1, 1.0)],
};
assert_eq!(
dijkstra::<WheightedAdjacencyList, BinaryHeap<_>, _>(&a, 0, |&n| n == 1),
Some(vec![0, 1])
);
}
#[test]
fn simple() {
let a = WheightedAdjacencyList {
nodes: vec![0, 2, 3, 5, 5, 7, 10],
edges: vec![
(1, 2.0),
(4, 10.0),
(2, 3.0),
(3, 2.0),
(5, 1.0),
(0, 4.0),
(2, 5.0),
(2, 9.0),
(3, 8.0),
(4, 0.0),
(5, 7.0),
],
};
assert_eq!(
dijkstra::<WheightedAdjacencyList, BinaryHeap<_>, _>(&a, 0, |&n| n == 4),
Some(vec![0, 1, 2, 5, 4])
);
assert_eq!(
dijkstra::<WheightedAdjacencyList, BinaryHeap<_>, _>(&a, 0, |&n| n == 6),
None
);
assert_eq!(
dijkstra::<WheightedAdjacencyList, FibonacciHeap<_>, _>(&a, 0, |&n| n == 4),
Some(vec![0, 1, 2, 5, 4])
);
assert_eq!(
dijkstra::<WheightedAdjacencyList, FibonacciHeap<_>, _>(&a, 0, |&n| n == 6),
None
);
}
struct Grid {
width: usize,
height: usize,
}
impl WheightedGraph for Grid {
type Node = (usize, usize);
fn num_edges(&self, node: &Self::Node) -> usize {
let mut c = 0;
if node.0 > 0 {
c += 1
}
if node.0 < self.width - 1 {
c += 1
}
if node.1 > 0 {
c += 1
}
if node.1 < self.height - 1 {
c += 1
}
c
}
fn edge(&self, node: &Self::Node, num: usize) -> Option<(Self::Node, f64)> {
dbg!(&node);
let edges = [
(node.0 > 0).then_some((node.0.saturating_sub(1), node.1)),
(node.0 < self.width - 1).then_some((node.0 + 1, node.1)),
(node.1 > 0).then_some((node.0, node.1.saturating_sub(1))),
(node.1 < self.height - 1).then_some((node.0, node.1 + 1)),
];
edges.iter().flatten().nth(num).map(|&p| (p, 1.0))
}
}
#[test]
fn grid() {
let g = Grid {
width: 600,
height: 600,
};
dbg!(dijkstra::<Grid, BinaryHeap<_>, _>(&g, (0, 0), |&n| n == (g.width - 1, g.height - 1)));
}
}

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@ -0,0 +1,17 @@
use crate::priority_queue::PriorityQueue;
use std::hash::Hash;
use std::{collections::HashSet, fmt::Debug};
use super::{WheightedGraph, shortest_path::QueueObject};
pub fn takaheshi_matsuyama<G, P>(graph: G, nodes: &[G::Node]) -> Option<Vec<Vec<G::Node>>>
where
P: PriorityQueue<QueueObject<G::Node>> + Debug,
P::Handle: Debug,
G::Node: Eq + Hash + Clone,
G: WheightedGraph,
{
let end_nodes: HashSet<G::Node> = HashSet::from_iter(nodes.iter().cloned());
todo!()
}