Struct MinimumExternalMacroDataCompression 

pub struct MinimumExternalMacroDataCompression { /* private fields */ }

Minimum External Macro Data Compression problem.

Given an alphabet of size k, a string s over {0, ..., k-1}, and a pointer cost h, find dictionary string D and compressed string C that minimize cost = |D| + |C| + (h-1) * (pointer count in C).

Representation

The configuration is a vector of 2 * string_length entries:

• First string_length entries are D-slots: each is a symbol index in {0, ..., alphabet_size-1} or alphabet_size (empty/unused).
• Next string_length entries are C-slots: each is:
  • A symbol index in {0, ..., alphabet_size-1} (literal)
  • alphabet_size (empty/unused)
  • A value in {alphabet_size+1, ..., alphabet_size + |s|*(|s|+1)/2} encoding a pointer (start, len) into D.

D is the prefix of non-empty D-slots. C is the prefix of non-empty C-slots. The cost is |D| + |C| + (h-1) * (number of pointer symbols in C).

Example

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

// Alphabet {a, b}, string "abab", pointer cost h=2
let problem = MinimumExternalMacroDataCompression::new(2, vec![0, 1, 0, 1], 2);
let solver = BruteForce::new();
let solution = solver.find_witness(&problem);
assert!(solution.is_some());

Implementations

impl MinimumExternalMacroDataCompression

pub fn new( alphabet_size: usize, string: Vec<usize>, pointer_cost: usize, ) -> Self

Create a new MinimumExternalMacroDataCompression instance.

Panics

Panics if alphabet_size is 0 and the string is non-empty, or if any symbol in the string is >= alphabet_size, or if pointer_cost is 0.

pub fn string_length(&self) -> usize

Returns the length of the source string.

pub fn alphabet_size(&self) -> usize

Returns the alphabet size.

pub fn pointer_cost(&self) -> usize

Returns the pointer cost h.

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

Returns the source string.

Trait Implementations

impl Clone for MinimumExternalMacroDataCompression

fn clone(&self) -> MinimumExternalMacroDataCompression

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MinimumExternalMacroDataCompression

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for MinimumExternalMacroDataCompression

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Problem for MinimumExternalMacroDataCompression

const NAME: &'static str = "MinimumExternalMacroDataCompression"

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

type Value = Min<usize>

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<usize>

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> for MinimumExternalMacroDataCompression

type Result = ReductionEMDCToILP

The reduction result type.

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

Reduce this problem to the target problem type.

impl Serialize for MinimumExternalMacroDataCompression

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 MinimumExternalMacroDataCompression