/*
 * Copyright (C) 2017 Christian Schilling (schillic@informatik.uni-freiburg.de)
 * Copyright (C) 2017 University of Freiburg
 *
 * This file is part of the ULTIMATE Util Library.
 *
 * The ULTIMATE Util Library is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * The ULTIMATE Util Library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with the ULTIMATE Util Library. If not, see <http://www.gnu.org/licenses/>.
 *
 * Additional permission under GNU GPL version 3 section 7:
 * If you modify the ULTIMATE Util Library, or any covered work, by linking
 * or combining it with Eclipse RCP (or a modified version of Eclipse RCP),
 * containing parts covered by the terms of the Eclipse Public License, the
 * licensors of the ULTIMATE Util Library grant you additional permission
 * to convey the resulting work.
 */
package de.uni_freiburg.informatik.ultimate.util.datastructures;

import java.util.Set;

/**
 * Simple interface for a partition of a finite set.
 * <p>
 * A partition is a collection of pairwise disjoint sets. Usually the union of all sets is considered the full set in a
 * given context, but this interface does not care about the union.
 * 
 * @author Christian Schilling (schillic@informatik.uni-freiburg.de)
 * @param <T>
 *            element type
 */
public interface IPartition<T> extends Iterable<Set<T>> {
	/**
	 * @param elem
	 *            Element.
	 * @return (unique) set (block) containing element
	 */
	Set<T> getContainingSet(final T elem);

	/**
	 * @return Number of elements (blocks) in the partition.
	 */
	int size();
}