Struct RuralPostman 

pub struct RuralPostman<G, W: WeightElement> { /* private fields */ }

The Rural Postman problem.

Given a weighted graph G = (V, E) with edge lengths l(e) and a subset E’ ⊆ E of required edges, find a minimum-cost circuit (closed walk) in G that includes each edge in E’.

Representation

Each edge is assigned a multiplicity variable:

• 0: edge is not traversed
• 1: edge is traversed once
• 2: edge is traversed twice

A valid circuit requires:

• All required edges have multiplicity ≥ 1
• All vertices have even degree (sum of multiplicities of incident edges)
• Edges with multiplicity > 0 form a connected subgraph

Note: In an optimal RPP solution on undirected graphs, each edge is traversed at most twice, so multiplicity ∈ {0, 1, 2} is sufficient.

Type Parameters

• G - The graph type (e.g., SimpleGraph)
• W - The weight type for edge lengths (e.g., i32, f64)

Implementations

impl<G: Graph, W: WeightElement> RuralPostman<G, W>

pub fn new(graph: G, edge_lengths: Vec<W>, required_edges: Vec<usize>) -> Self

Create a new RuralPostman problem.

Panics

Panics if edge_lengths length does not match graph edges, or if any required edge index is out of bounds.

pub fn graph(&self) -> &G

Get a reference to the underlying graph.

pub fn edge_lengths(&self) -> &[W]

Get the edge lengths.

pub fn required_edges(&self) -> &[usize]

Get the required edge indices.

pub fn num_vertices(&self) -> usize

Get the number of vertices in the underlying graph.

pub fn num_edges(&self) -> usize

Get the number of edges in the underlying graph.

pub fn num_required_edges(&self) -> usize

Get the number of required edges.

pub fn set_weights(&mut self, weights: Vec<W>)

Set new edge lengths.

pub fn weights(&self) -> Vec<W>

Get the edge lengths as a Vec.

pub fn is_weighted(&self) -> bool

Check if the problem uses a non-unit weight type.

pub fn is_valid_solution(&self, config: &[usize]) -> Option<W::Sum>

Check if a configuration represents a valid circuit covering all required edges. Returns Some(cost) if valid, None otherwise.

Each config[i] is the multiplicity (number of traversals) of edge i.

Trait Implementations

impl<G: Clone, W: Clone + WeightElement> Clone for RuralPostman<G, W>

fn clone(&self) -> RuralPostman<G, W>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<G: Debug, W: Debug + WeightElement> Debug for RuralPostman<G, W>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de, G, W> Deserialize<'de> for RuralPostman<G, W>

where G: Deserialize<'de>, W: Deserialize<'de> + WeightElement,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<G, W> Problem for RuralPostman<G, W>

where G: Graph + VariantParam, W: WeightElement + VariantParam,

const NAME: &'static str = "RuralPostman"

Base name of this problem type (e.g., “MaximumIndependentSet”).

type Value = Min<<W as WeightElement>::Sum>

The evaluation value type.

fn variant() -> Vec<(&'static str, &'static str)>

Returns variant attributes derived from type parameters.

fn dims(&self) -> Vec<usize>

Configuration space dimensions. Each entry is the cardinality of that variable.

fn evaluate(&self, config: &[usize]) -> Min<W::Sum>

Evaluate the problem on a configuration.

fn num_variables(&self) -> usize

Number of variables (derived from dims).

fn problem_type() -> ProblemType

Look up this problem’s catalog entry.

impl ReduceTo<ILP<i32>> for RuralPostman<SimpleGraph, i32>

type Result = ReductionRPToILP

The reduction result type.

fn reduce_to(&self) -> Self::Result

Reduce this problem to the target problem type.

impl ReduceTo<RuralPostman<SimpleGraph, i32>> for HamiltonianCircuit<SimpleGraph>

type Result = ReductionHamiltonianCircuitToRuralPostman

The reduction result type.

fn reduce_to(&self) -> Self::Result

Reduce this problem to the target problem type.

impl<G, W> Serialize for RuralPostman<G, W>

where G: Serialize, W: Serialize + WeightElement,

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl DeclaredVariant for RuralPostman<SimpleGraph, i32>