链队列的实现

   //接口
   public interface IQueue<T>
    {
        int GetLength(); //求队列的长度
        bool IsEmpty(); //判断对列是否为空
        void Clear(); //清空队列
        void In(T item); //入队
        T Out(); //出队
        T GetFront(); //取对头元素
    }
   //接口的实现
   public class LinkQueue<T> : IQueue<T>
    {
        private Node<T> front; //队列头指示器
        private Node<T> rear; //队列尾指示器
        private int num; //队列结点个数

        //队头属性
        public Node<T> Front
        {
            get
            {
                return front;
            }
            set
            {
                front = value;
            }
        }
        //队尾属性
        public Node<T> Rear
        {
            get
            {
                return rear;
            }
            set
            {
                rear = value;
            }
        }
        //队列结点个数属性
        public int Num
        {
            get
            {
                return num;
            }
            set
            {
                num = value;
            }
        }
        //构造器
        public LinkQueue()
        {
            front = rear = null;

            num = 0;
        }
        //求链队列的长度
        public int GetLength()
        {
            return num;
        }
        //清空链队列
        public void Clear()
        {
            front = rear = null;
            num = 0;
        }
        //判断链队列是否为空
        public bool IsEmpty()
        {
            if ((front == rear) && (num == 0))
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        //入队
        public void In(T item)
        {
            Node<T> q = new Node<T>(item);
            if (rear == null)
            {
                rear = q;
            }
            else
            {
                rear.Next = q;
                rear = q;
            }
            ++num;
        }
        //出队
        public T Out()
        {
            if (IsEmpty())
            {
                Console.WriteLine("Queue is empty!");
                return default(T);
            }
            Node<T> p = front;
            front = front.Next;
            if (front == null)
            {
                rear = null;
            }
            --num;
            return p.Data;
        }
        //获取链队列头结点的值
        public T GetFront()
        {
            if (IsEmpty())
            {
                Console.WriteLine("Queue is empty!");
                return default(T);
            }
            return front.Data;
        }
    }