//queue.cs
class MyQueue
{
//存放元素的数组
private object[] _array;
//增长因子
private int _growFactor;
//队头下标
private int _head;
//队尾下标
private int _tail;
private int _size;
private const int _MinGrow = 4;
//初始容量
private const int _ShrikThreadhold = 0x20;
public MyQueue()
: this(_ShrikThreadhold, 2f) { }
public MyQueue(int capacity, float growFactor)
{
if (capacity < 0)
{
throw new ArgumentOutOfRangeException("capacity", "初始容量不能为负！");
}
if ((growFactor < 1.0) || (growFactor > 10))
{
throw new ArgumentOutOfRangeException("growFactor", "增长因子应介于1和10之间!");
}
this._array = new object[capacity];
this._head = 0;
this._size = 0;
this._tail = 0;
this._growFactor = (int)(growFactor * 100f);
}
//入队
public virtual void Enqueue(object obj)
{
if (this._size == this._array.Length)
{//队列已满
int capacity = (int)((this._array.Length * this._growFactor) / 100L);
if (capacity < (this._array.Length + _MinGrow))
{
capacity = this._array.Length + _MinGrow;
}
SetCapacity(capacity);
}
this._array[this._tail] = obj;
this._tail = (this._tail + 1) % this._array.Length;
this._size++;
}
//内存设置
private void SetCapacity(int capacity)
{
object[] dest = new object[capacity];
if (this._head < this._tail)//尾指针在头指针后
{
Array.Copy(this._array, this._head, dest, 0, this._size);
}
else//头指针在尾指针后
{
Array.Copy(this._array, this._head, dest, 0, this._array.Length - this._head);
Array.Copy(this._array, 0, dest, this._array.Length - this._head, this._tail);
}
this._array = dest;
this._head = 0;
this._tail = (this._size == capacity) ? 0 : this._size;
}
//出队
public virtual object Dequeue()
{
if (this._size == 0)
{
throw new InvalidOperationException("队列为空");
}
object obj = this._array[this._head];//出队
this._array[this._head] = null;
this._head = (this._head + 1) % this._array.Length;
this._size--;
return obj;
}
public virtual int Count
{
get { return this._size; }
}
}
//测试类
static void Main(string[] args)
{
Program main = new Program();
main.testQueue();
}
private void testQueue()
{
Queue<int> myQueue = new Queue<int>();
//MyQueue myQueue = new MyQueue();//与上面类使用一样
myQueue.Enqueue(1);
myQueue.Enqueue(2);
myQueue.Enqueue(3);
myQueue.Enqueue(4);
Console.WriteLine("总数量："+myQueue.Count.ToString());
while (myQueue.Count > 0)
{
Console.WriteLine("出列："+myQueue.Dequeue());
}
Console.WriteLine("数量："+myQueue.Count.ToString());
Console.ReadLine();
}
效果：
