Struct LongestPath 

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

The Longest Path problem.

Given a graph G = (V, E) with positive edge lengths l(e) and distinguished vertices s and t, find a simple path from s to t maximizing the total length of its selected edges.

Representation

Each edge is assigned a binary variable:

• 0: the edge is not selected
• 1: the edge is selected

A valid configuration must select exactly the edges of one simple undirected path from source_vertex to target_vertex.

Implementations

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

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

Create a new LongestPath instance.

pub fn graph(&self) -> &G

Get a reference to the underlying graph.

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

Get the edge lengths.

pub fn set_lengths(&mut self, edge_lengths: Vec<W>)

Replace the edge lengths with a new vector.

pub fn source_vertex(&self) -> usize

Get the source vertex.

pub fn target_vertex(&self) -> usize

Get the target vertex.

pub fn is_weighted(&self) -> bool

Check whether this problem uses non-unit edge lengths.

pub fn num_vertices(&self) -> usize

Get the number of vertices in the graph.

pub fn num_edges(&self) -> usize

Get the number of edges in the graph.

pub fn is_valid_solution(&self, config: &[usize]) -> bool

Check if a configuration encodes a valid simple source-target path.

Trait Implementations

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

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

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

Formats the value using the given formatter.

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

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

const NAME: &'static str = "LongestPath"

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

type Value = Max<<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]) -> Max<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 LongestPath<SimpleGraph, i32>

type Result = ReductionLongestPathToILP

The reduction result type.

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

Reduce this problem to the target problem type.

impl ReduceTo<LongestPath<SimpleGraph, One>> for HamiltonianPathBetweenTwoVertices<SimpleGraph>

type Result = ReductionHPBTVToLP

The reduction result type.

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

Reduce this problem to the target problem type.

impl<G, W> Serialize for LongestPath<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 LongestPath<SimpleGraph, One>

impl DeclaredVariant for LongestPath<SimpleGraph, i32>