dequeue

Node dequeue(Node heap[])
{
    if(array_size == 0)
    {
        printf("heap is empty\n");
        return -123456789;
    }
    Node t;
    t = heap[0];
    Swap(&heap[0],&heap[array_size-1]);
    array_size = array_size-1;
    heapifyroot(heap);
    return t;
}

void heapifyroot(Node heap[])
{
    int i = 0;
    while(i< (array_size)/2 && (heap[i].priority <= heap[2*i+1].priority || heap[i].priority <= heap[2*i+2].priority))
    {
        if(heap[2*i+1].priority < heap[2*i+2].priority)
        {
            Swap(&heap[0],&heap[2*i+2]);
            i = 2*i+2;
        }
        else if(heap[2*i+1].priority > heap[2*i+2].priority)
        {
            Swap(&heap[0],&heap[2*i+1]);
            i = 2*i+1;
        }
        else
        {
            if(heap[2*i+1].priority2 > heap[2*i+2].priority2)
            {
                Swap(&heap[0],&heap[2*i+2]);
                i = 2*i+2;
            }
            else
            {
                Swap(&heap[0],&heap[2*i+1]);
                i = 2*i+1;
            }
        }
    }
    return;
}