堆排序演算法

Code
  #region   堆排序（第0個資料不能排序）
    static    private void Sift(int[] r, int i, int m)
        {
            int j;
            int temp;
            temp = r[i];
            j = 2 * i;
            while (j <= m)
            {
                if (j < m && r[j] < r[j + 1])
                {
                    j++;
                }
                if (temp < r[j])
                {
                    r[i] = r[j];
                    i = j;
                    j = 2 * i;
                }
                else
                {
                    break;
                }
            }
            r[i] = temp;
        }

        /// <summary>
        /// 堆排序
        /// </summary>
        /// <param name="r">資料來源</param>
        /// <param name="n">元素個數</param>
      static  public void HeapSort(int[] r, int n)
        {
            int temp;
            int i;
            for (i = n / 2; i >= 1; i--)
            {
                Sift(r, i, n);
            }
            for (i = n; i >= 2; i--)
            {
                temp = r[1];
                r[1] = r[i];
                r[i] = temp;
                Sift(r, 1, i - 1);
            }
        }

        #endregion