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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.hyracks.dataflow.std.structures;

public class MinHeap extends AbstractHeap implements IMinHeap {

    public MinHeap(IResetableComparableFactory factory, int capacity) {
        super(factory, capacity);
    }

    @Override
    protected void bubbleUp(int i) {
        int pid = getParentId(i);
        if (pid != NOT_EXIST && compareTo(pid, i) > 0) {
            swap(pid, i);
            bubbleUp(pid);
        }
    }

    @Override
    protected void trickleDown(int i) {
        int minChild = getMinChild(i);
        if (minChild != NOT_EXIST && compareTo(i, minChild) > 0) {
            swap(minChild, i);
            trickleDown(minChild);
        }
    }

    @Override
    public void getMin(IResetableComparable result) {
        result.reset(entries[0]);
        numEntry--;
        if (numEntry > 0) {
            entries[0].reset(entries[numEntry]);
            trickleDown(0);
        }
    }

    @Override
    public void peekMin(IResetableComparable result) {
        result.reset(entries[0]);
    }

    @Override
    public void replaceMin(IResetableComparable newElement) {
        entries[0].reset(newElement);
        trickleDown(0);
    }
}