Module list_change 

List change move selector for element relocation.

Generates ListChangeMoves that relocate elements within or between list variables. Essential for vehicle routing and scheduling problems.

Example

use solverforge_solver::heuristic::selector::list_change::ListChangeMoveSelector;
use solverforge_solver::heuristic::selector::entity::FromSolutionEntitySelector;
use solverforge_solver::heuristic::selector::MoveSelector;
use solverforge_core::domain::PlanningSolution;
use solverforge_core::score::SimpleScore;

#[derive(Clone, Debug)]
struct Vehicle { visits: Vec<i32> }

#[derive(Clone, Debug)]
struct Solution { vehicles: Vec<Vehicle>, score: Option<SimpleScore> }

impl PlanningSolution for Solution {
    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: &Solution, entity_idx: usize) -> usize {
    s.vehicles.get(entity_idx).map_or(0, |v| v.visits.len())
}
fn list_remove(s: &mut Solution, entity_idx: usize, pos: usize) -> Option<i32> {
    s.vehicles.get_mut(entity_idx).map(|v| v.visits.remove(pos))
}
fn list_insert(s: &mut Solution, entity_idx: usize, pos: usize, val: i32) {
    if let Some(v) = s.vehicles.get_mut(entity_idx) { v.visits.insert(pos, val); }
}

let selector = ListChangeMoveSelector::<Solution, i32, _>::new(
    FromSolutionEntitySelector::new(0),
    list_len,
    list_remove,
    list_insert,
    "visits",
    0,
);

Structs

ListChangeMoveSelector

A move selector that generates list change moves.