Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
menu search
person
Welcome To Ask or Share your Answers For Others

Categories

I'm studying heap & heap sorting.
There is a array : arr[8] = {6,9,3,1,8,7,2,11}
When I'm trying to build the heap, using code and pencil, I faced two kinds of heap.

When using code, MaxHeap : 11 9 7 6 8 3 2 1

When using insertion theory, MaxHeap : 11 9 7 8 6 3 2 1


The code that i'm using :

int[] DoHeapSort(int[] value) {
    int length = value.length;

    for (int i = length / 2; i > 0; i--) {
        maxHeapify(value, i, length);
    }

    //print Heap
    for(int i = 0 ; i<value.length; i++)
        System.out.println(value[i]);


    return (value);
}


void maxHeapify(int[] array, int index, int heapSize) {
    int left = index * 2;
    int right = left + 1;
    int max = index;

    if (left <= heapSize && array[left - 1] > array[index - 1]) {
        max = left;
    }

    if (right <= heapSize && array[right - 1] > array[max - 1]) {
        max = right;
    }

    if (max != index) {
        swap(array, index - 1, max - 1);
        maxHeapify(array, max, heapSize);
    }
}

Theory, in this case, create another array for heap and insert from 6 to 11 in order. (On the other hand, code is in-place heap)

Both maxHeap results satisfied heap definition. Then Heap is not unique ? Thanks

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
1.0k views
Welcome To Ask or Share your Answers For Others

1 Answer

That's correct. The heap constraint (which is that children are not greater than their parents) does not completely specify the heap, so there is usually more than one possible arrangement.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
thumb_up_alt 0 like thumb_down_alt 0 dislike
Welcome to ShenZhenJia Knowledge Sharing Community for programmer and developer-Open, Learning and Share
...