Struct ListRuinMove 

pub struct ListRuinMove<S, V> { /* private fields */ }

A move that removes elements from a list for Large Neighborhood Search.

Elements are removed by index and stored for reinsertion by a construction heuristic. This is the list-variable equivalent of RuinMove.

Type Parameters

• S - The planning solution type
• V - The list element value type

Example

use solverforge_solver::heuristic::r#move::ListRuinMove;
use solverforge_core::domain::PlanningSolution;
use solverforge_core::score::SimpleScore;

#[derive(Clone, Debug)]
struct Route { stops: Vec<i32>, score: Option<SimpleScore> }

impl PlanningSolution for Route {
    type Score = SimpleScore;
    fn score(&self) -> Option<Self::Score> { self.score }
    fn set_score(&mut self, score: Option<Self::Score>) { self.score = score; }
}

fn list_len(s: &Route, _: usize) -> usize { s.stops.len() }
fn list_remove(s: &mut Route, _: usize, idx: usize) -> i32 { s.stops.remove(idx) }
fn list_insert(s: &mut Route, _: usize, idx: usize, v: i32) { s.stops.insert(idx, v); }

// Remove elements at indices 1 and 3 from the route
let m = ListRuinMove::<Route, i32>::new(
    0,
    &[1, 3],
    list_len, list_remove, list_insert,
    "stops", 0,
);

Implementations

impl<S, V> ListRuinMove<S, V>

pub fn new( entity_index: usize, element_indices: &[usize], list_len: fn(&S, usize) -> usize, list_remove: fn(&mut S, usize, usize) -> V, list_insert: fn(&mut S, usize, usize, V), variable_name: &'static str, descriptor_index: usize, ) -> Self

Creates a new list ruin move with typed function pointers.

Arguments

• entity_index - Entity index
• element_indices - Indices of elements to remove
• list_len - Function to get list length
• list_remove - Function to remove element at index
• list_insert - Function to insert element at index
• variable_name - Name of the list variable
• descriptor_index - Entity descriptor index

Note

Indices are sorted internally for correct removal order.

pub fn entity_index(&self) -> usize

Returns the entity index.

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

Returns the element indices being removed.

pub fn ruin_count(&self) -> usize

Returns the number of elements being removed.

Trait Implementations

impl<S, V> Clone for ListRuinMove<S, V>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<S, V: Debug> Debug for ListRuinMove<S, V>

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

Formats the value using the given formatter.

impl<S, V> Move<S> for ListRuinMove<S, V>

where S: PlanningSolution, V: Clone + Send + Sync + Debug + 'static,

fn is_doable<D: ScoreDirector<S>>(&self, score_director: &D) -> bool

Returns true if this move can be executed in the current state.

fn do_move<D: ScoreDirector<S>>(&self, score_director: &mut D)

Executes this move, modifying the working solution.

fn descriptor_index(&self) -> usize

Returns the descriptor index of the entity type this move affects.

fn entity_indices(&self) -> &[usize]

Returns the entity indices involved in this move.

fn variable_name(&self) -> &str

Returns the variable name this move affects.

impl<S, V> MoveSelector<S, ListRuinMove<S, V>> for ListRuinMoveSelector<S, V>

where S: PlanningSolution, V: Clone + Send + Sync + Debug + 'static,

fn iter_moves<'a, D: ScoreDirector<S>>( &'a self, score_director: &'a D, ) -> Box<dyn Iterator<Item = ListRuinMove<S, V>> + 'a>

Returns an iterator over typed moves.

fn size<D: ScoreDirector<S>>(&self, score_director: &D) -> usize

Returns the approximate number of moves.

fn is_never_ending(&self) -> bool

Returns true if this selector may return the same move multiple times.