PairHeapDecrKey.java

/*******************************************************************************
 * Copyright (c) 2012-present Jakub Kováč, Jozef Brandýs, Katarína Kotrlová,
 * Pavol Lukča, Ladislav Pápay, Viktor Tomkovič, Tatiana Tóthová
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ******************************************************************************/
package algvis.ds.priorityqueues.pairingheap;

import algvis.ui.InputField;

public class PairHeapDecrKey extends PairHeapAlg {
    private final int delta;

    public PairHeapDecrKey(PairingHeap D, PairHeapNode v, int delta) {
        super(D);
        this.v = v;
        this.delta = delta;
    }

    @Override
    public void runAlgorithm() {
        setHeader(H.minHeap ? "decreasekey" : "increasekey");
        if (H.minHeap) {
            v.setKey(v.getKey() - delta);
            if (v.getKey() < 1) {
                v.setKey(1);
            }
        } else {
            v.setKey(v.getKey() + delta);
            if (v.getKey() > InputField.MAX) {
                v.setKey(InputField.MAX);
            }
        }
        if (!v.isRoot()) {
            if (H.minHeap) {
                addStep("pairdecr"); // zvysili sme hodnotu, dieta odtrhneme a
                // prilinkujeme
            } else {
                addStep("pairincr");
            }
            H.root[0] = v;
            H.root[0].mark();
            pause();
            v.getParent().deleteChild(v);

            H.root[H.active].mark();
            H.reposition();
            pause();
            H.root[0].unmark();
            H.root[H.active].unmark();
            link(H.active, 0);
            H.root[0] = null;
            H.reposition();
        }

        addNote("done");
    }
}