static void Main(string[] args)
{
Console.WriteLine("Enter the number of elements in queue:");
var input = Console.ReadLine();
MaxPQ <string> pq;
int number;
while (!int.TryParse(input, out number))
{
Console.WriteLine("Enter a valid number:");
input = Console.ReadLine();
}
pq = new MaxPQ <string>(number);
while (number > 0)
{
Console.WriteLine("Enter keys");
string entry = Console.ReadLine();
pq.Insert(entry);
number--;
}
while (!pq.IsEmpty)
{
Console.WriteLine(pq.DeleteMax());
}
}
/// <summary>
/// 根据指定数组初始化面向中位数的堆。
/// </summary>
/// <param name="keys">初始数组。</param>
public MedianPQ(Key[] keys)
{
minPQ = new MinPQ <Key>();
maxPQ = new MaxPQ <Key>();
if (keys.Length == 0)
{
n = 0;
median = default(Key);
return;
}
n = keys.Length;
median = keys[0];
for (var i = 1; i < keys.Length; i++)
{
if (median.CompareTo(keys[i]) < 0)
{
minPQ.Insert(keys[i]);
}
else
{
maxPQ.Insert(keys[i]);
}
}
UpdateMedian();
}
/// <summary>
/// 插入一个新的值。
/// </summary>
/// <param name="v">待插入的新值。</param>
public void Insert(Key v)
{
n++;
MinMaxNode.GetNodes(v, n, out var minNode, out var maxNode);
maxPQ.Insert(maxNode);
minPQ.Insert(minNode);
}
/// <summary>
/// 向面向中位数的堆中插入一个元素。
/// </summary>
/// <param name="key">需要插入的元素。</param>
public void Insert(Key key)
{
if (n == 0)
{
n++;
median = key;
return;
}
if (key.CompareTo(median) < 0)
{
maxPQ.Insert(key);
}
else
{
minPQ.Insert(key);
}
n++;
UpdateMedian();
}
/// <summary>
/// 获取堆的迭代器，元素以降序排列。
/// </summary>
/// <returns></returns>
public IEnumerator <Key> GetEnumerator()
{
MaxPQ <Key> copy = new MaxPQ <Key>(this.n);
for (int i = 1; i <= this.n; i++)
{
copy.Insert(this.pq[i]);
}
while (!copy.IsEmpty())
{
yield return(copy.DelMax()); // 下次迭代的时候从这里继续执行。
}
}
/// <summary>
/// 获取堆的迭代器，元素以降序排列。
/// </summary>
/// <returns>最大堆的迭代器。</returns>
public IEnumerator <Key> GetEnumerator()
{
var copy = new MaxPQ <Key>(n);
for (var i = 1; i <= n; i++)
{
copy.Insert(pq[i]);
}
while (!copy.IsEmpty())
{
yield return(copy.DelMax()); // 下次迭代的时候从这里继续执行。
}
}
