DaryHeapDelete.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.daryheap;

import algvis.core.Node;

public class DaryHeapDelete extends DaryHeapAlg {
    public DaryHeapDelete(DaryHeap H) {
        super(H);
    }

    @Override
    public void runAlgorithm() {
        setHeader(H.minHeap ? "delete-min" : "delete-max");
        if (H.root == null) {
            addStep("heapempty");
            H.last = null;
            return;
        }

        if (H.root.c.size() == 0) {
            final DaryHeapNode v = H.root;
            if (H.minHeap) {
                addStep("minimum", H.root.getKey());
            } else {
                addStep("maximum", H.root.getKey());
            }
            H.root = null;
            addToScene(v);
            v.mark();
            // --H.n;
            pause();
            v.unmark();
            v.goDown();
            removeFromScene(v);
            return;
        }
        if (H.minHeap) {
            addStep("minimum", H.root.getKey());
        } else {
            addStep("maximum", H.root.getKey());
        }
        H.root.mark();
        pause();
        // H.root.unmark();
        addStep("heapchange");
        pause();
        H.root.unmark();

        DaryHeapNode v = new DaryHeapNode(H.last);
        final DaryHeapNode v2 = new DaryHeapNode(H.root);
        addToScene(v);
        addToScene(v2);
        H.last.setKey(Node.NOKEY);
        H.root.setKey(Node.NOKEY);
        v.goToRoot();
        v2.goTo(H.last);
        v2.mark();
        pause();
        H.last.setKey(v2.getKey());
        H.root.setKey(v.getKey());
        H.last.setColor(v2.getColor());
        H.root.setColor(v.getColor());
        removeFromScene(v);
        removeFromScene(v2);

        v = H.last;
        addToScene(v);
        H.last = H.last.prevneighbour();
        v.goDown();
        removeFromScene(v);
        v.getParent().c.set(v.nson - 1, null);
        v.getParent().c.setSize(v.getParent().c.size() - 1);
        H.root.mark();
        H.reposition();

        if (H.minHeap) {
            addStep("mindheapbubbledown");
        } else {
            addStep("maxdheapbubbledown");
        }
        pause();

        H.root.unmark();
        bubbledown(H.root);
    }
}