Problem:
MathJax.Hub.Config({ tex2jax: { inlineMath: [["$","$"], ["\\(","\\)"]], processEscapes: true }});

Maximum Heap

A binary heap which satisfies max-heap property is called max-heap. In a max-heap, for every node $i$ other than the root, $A[i] \leq A[parent(i)]$, that is, the value of a node is at most the value of its parent. The largest element in a max-heap is stored at the root, and the subtree rooted at a node contains values no larger than that contained at the node itself.

Here is an example of a max-heap.

Write a program which reads an array and constructs a max-heap from the array based on the following pseudo code.

$maxHeapify(A, i)$ move the value of $A[i]$ down to leaves to make a sub-tree of node $i$ a max-heap. Here, $H$ is the size of the heap.

1 maxHeapify(A, i)
2 l = left(i)
3 r = right(i)
4 // select the node which has the maximum value
5 if l ≤ H and A[l] > A[i]
6 largest = l
7 else
8 largest = i
9 if r ≤ H and A[r] > A[largest]
10 largest = r
11
12 if largest ≠ i　// value of children is larger than that of i
13 swap A[i] and A[largest]
14 maxHeapify(A, largest) // call recursively

The following procedure buildMaxHeap(A) makes $A$ a max-heap by performing maxHeapify in a bottom-up manner.

1 buildMaxHeap(A)
2 for i = H/2 downto 1
3 maxHeapify(A, i)

Input

In the first line, an integer $H$ is given. In the second line, $H$ integers which represent elements in the binary heap are given in order of node id (from $1$ to $H$).

Output

Print values of nodes in the max-heap in order of their id (from $1$ to $H$). Print a single space character before each value.

Constraint

$1 \leq H \leq 500,000$

$-2,000,000,000 \leq$ value of a node $\leq 2,000,000,000$

Sample Input 1

10
4 1 3 2 16 9 10 14 8 7

Sample Output 1

16 14 10 8 7 9 3 2 4 1

Reference

Introduction to Algorithms, Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. The MIT Press.

Solution in C# (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace _20170410_AOJ
{
    class ALDS1_9B
    {
        static void Main(string[] args)
        {
            for (;;)
            {
                string line = Console.ReadLine();
                if (string.IsNullOrEmpty(line))
                {
                    break;
                }

                int n = int.Parse(line);
                int[] A = new int[n + 1];

                int[] vals = Console.ReadLine().Split(' ').Select(x => int.Parse(x)).ToArray();
                Array.Copy(vals, 0, A, 1, n);

                BuildMaxHeap(A);
                WriteArray(A);
            }
        }

        static void WriteArray(int[] A)
        {
            StringBuilder sb = new StringBuilder();
            for (int i = 1; i < A.Length; i++)
            {
                sb.Append(' ');
                sb.Append(A[i]);
            }

            Console.WriteLine(sb.ToString());
        }

        static void MaxHeapify(int[] A, int i)
        {
            int l = i * 2;
            int r = l + 1;
            int h = A.Length - 1;
            int largest = 0;

            if (l <= h && A[l] > A[i])
            {
                largest = l;
            }
            else
            {
                largest = i;
            }

            if (r <= h && A[r] > A[largest])
            {
                largest = r;
            }

            if (largest != i)
            {
                int temp = A[i];
                A[i] = A[largest];
                A[largest] = temp;
                MaxHeapify(A, largest);
            }
        }

        static void BuildMaxHeap(int[] A)
        {
            int h = A.Length - 1;
            for (int i = h / 2; i >= 1; i--)
            {
                MaxHeapify(A, i);
            }
        }
    }
}