Struct SubsetProduct 

pub struct SubsetProduct { /* private fields */ }

The Subset Product problem.

Given a set of n positive integers and a target B, determine whether there exists a subset whose elements multiply to exactly B.

Representation

Each element has a binary variable: x_i = 1 if element i is selected, 0 otherwise. The problem is satisfiable iff ∏_{i: x_i=1} sizes[i] == target.

Example

use problemreductions::models::misc::SubsetProduct;
use problemreductions::{Problem, Solver, BruteForce};

let problem = SubsetProduct::new(vec![2u32, 3, 5, 7, 6, 10], 210u32);
let solver = BruteForce::new();
let solution = solver.find_witness(&problem);
assert!(solution.is_some());

Implementations

impl SubsetProduct

pub fn new<S, T>(sizes: Vec<S>, target: T) -> Self

where S: ToBigUint, T: ToBigUint,

Create a new SubsetProduct instance.

Panics

Panics if any size is not positive (must be > 0) or if target is zero.

pub fn sizes(&self) -> &[BigUint]

Returns the element sizes.

pub fn target(&self) -> &BigUint

Returns the target product.

pub fn num_elements(&self) -> usize

Returns the number of elements.

Trait Implementations

impl Clone for SubsetProduct

fn clone(&self) -> SubsetProduct

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SubsetProduct

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for SubsetProduct

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Problem for SubsetProduct

const NAME: &'static str = "SubsetProduct"

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

type Value = Or

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]) -> Or

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<SubsetProduct> for ExactCoverBy3Sets

type Result = ReductionX3CToSubsetProduct

The reduction result type.

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

Reduce this problem to the target problem type.

impl Serialize for SubsetProduct

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 SubsetProduct