建立大根堆的算法

#include
using namespace std;

void MakeHeap (int a[], int n);

int
main ()
{
  int a[100];
  int n, i;

  cout << "Enter the number:" << endl;
  cin >> n;

  for (i = 1; i <= n; i++)
    {
      cout << "Enter the element of the Heap:" << endl;
      cin >> a[i];
    }

  MakeHeap (a, n);

  cout << "The Heap is:" << endl;
  for (i = 1; i <= n; i++)
    {
      cout << a[i] << " ";
    }

  cout << endl;

  return 1;
}

void
MakeHeap (int a[], int n)
{
  int i, j, flag;

  for (i = n / 2; i >= 1; i--)
    {
      j = 2 * i;
      if (a[j] <= a[j + 1])
    j++;
      if (a[i] < a[j])
    {
      flag = a[i];
      a[i] = a[j];
      a[j] = flag;
    }
    }
}