为什么我的 Max Heap Heapsort 方法不起作用？

Question

So I'm working with the java implementation of Max Heaps. My Insert, bubbleUp and deleteMax (on its own) methods seem to work fine, but my heapsort method (which calls deleteMax) doesn't work as its supposed to (it doesn't cause an error message; it just doesn't sort them in the order it's supposed to). I've included the code below. Any help understanding the problem is greatly appreciated. Thanks!

The whole class can be found at: https://repl.it/repls/FrequentPartialBlockchain

'''

    public int deleteMax(){
        if(this.numNodes == 0)
            throw new NoSuchElementException();
        else if(this.numNodes == 1){
            int elemToReturn = heapArr[0];
            heapArr[0] = null;
            return elemToReturn;
        }

        int elemToReturn = heapArr[0];
        heapArr[0] = heapArr[numNodes-1];
        heapArr[numNodes-1] = null;
        this.numNodes--;
        bubbleDown();
        return elemToReturn;
    }

    private void bubbleDown(){
        int n = 0;
        int L = 2 * n + 1; // L will hold the index of the left child
        while(L < this.numNodes - 1){
            int max = L;
            int R = L + 1; // R will hold the index of the right child

            if(R < this.numNodes - 1){
                if(heapArr[R] >= heapArr[L])
                    max++;
            }
            int temp;
            if(heapArr[n] < heapArr[max]){
                // swap
                temp = heapArr[n];
                heapArr[n] = heapArr[max];
                heapArr[max] = temp;

                n = max;
                L = 2 * n + 1;
            }
            else{
                break;
            }
        }
    }

    public static void heapsort(Integer[] arrayToSort){
        MaxHeap tempHeap = new MaxHeap(arrayToSort);
        for(int i = 0; i < tempHeap.numNodes; i++)
            arrayToSort[i] = (Integer) tempHeap.deleteMax();
    }

'''

Answer 1

This while statement seems wrong:

while(L < this.numNodes - 1){

If this.numNodes is the number of nodes in the heap, then this.numNodes - 1 is the last node. This condition, then, prevents the loop from being entered if L is the last node in the heap.

On a related note, your special case in deletMax is broken. You remove the only node in the heap, but you forgot to set numNodes to 0.