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Triple Loop

Evaluates rotating a triplet of objects in a cycle across three containers, and keeps the best such rotation. This can escape local minima that pairwise Swap cannot.

Triple loop move: three objects rotate in a cycle across the hot container and two other containers

Parameters​

TripleLoopMoveTypeSpec takes no parameters. To bound exploration time per hot container, set timePerMove on the LocalSearchSolverSpec.

Behavior​

Given the hot container chosen by the common logic:

  1. Pick one object from the hot container (the "hot object").
  2. Pick an object in another container (the "other object 1").
  3. Pick an object in a third container (the "other object 2").
  4. Evaluate, all at once, rotating them: the hot object to other object 1's container, other object 1 to other object 2's container, and other object 2 to the hot container.

Every such triplet is evaluated and the best rotation is selected.

Complexity​

Roughly objects ^ 3 neighbors are evaluated.

Example​

Configure local search to use only the triple loop move type:

LocalSearchSolverSpec localSearch;
localSearch.moveTypeList()->push_back(
    ProblemSolver::makeMoveTypeSpec(TripleLoopMoveTypeSpec()));

solver.addSolver(localSearch);

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