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Java Tools for parsing XCSP3 instances, compiling JvCSP3 models, and checking solutions. For more information about XCSP3, follow www.xcsp.org

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/**
 * AbsCon - Copyright (c) 2017, CRIL-CNRS - [email protected]
 * 
 * All rights reserved.
 * 
 * This program and the accompanying materials are made available under the terms of the CONTRAT DE LICENCE DE LOGICIEL LIBRE CeCILL which accompanies this
 * distribution, and is available at http://www.cecill.info
 */
package org.xcsp.modeler.problems;

import org.xcsp.common.IVar.Var;
import org.xcsp.modeler.api.ProblemAPI;

public class Blackhole implements ProblemAPI {

	int nCardsPerSuit, nCardsPerPile; // todo removing redundant nCardsPerPile
	int[][] piles;

	@Override
	public void model() {
		int nCards = 4 * nCardsPerSuit, nPiles = (nCards - 1) / nCardsPerPile;

		Var[] x = array("x", size(nCards), dom(range(nCards)), "x[i] is the value j of the card at the ith position of the built stack.");
		Var[] y = array("y", size(nCards), dom(range(nCards)), "y[j] is the position i of the card whose value is j");

		channel(x, y);
		equal(y[0], 0).note("the Ace of Spades is initially put on the stack");

		forall(range(nPiles), i -> ordered(variablesFrom(piles[i], j -> y[j]), STRICTLY_INCREASING)).note("cards must be played in the order of the piles");

		int[][] tuples = range(nCards).range(nCards)
				.select((i, j) -> i % nCardsPerSuit == (j + 1) % nCardsPerSuit || j % nCardsPerSuit == (i + 1) % nCardsPerSuit);
		slide(x, range(nCards - 1), i -> extension(vars(x[i], x[i + 1]), tuples))
				.note("each new card put on the stack must be at a rank higher or lower than the previous one.");
	}
}