数据结构之队列应用

   队列为循环队列，使用循环队列的原因是：防止假溢出。

 

  1using System;
  2using System.Collections.Generic;
  3using System.Text;
  4
  5namespace 队列应用
  6{
  7    class Program
  8    {
  9        public interface IQueue<T>
 10        { 
 11           //求队列的长度
 12            int GetLength();
 13           //判断队列是否为空
 14            bool IsEmpty();
 15           //清空队列
 16            void Clear();
 17           //入队
 18            void In(T item);
 19           //出队
 20            T Out();
 21           //取对头元素
 22            T GetFront();
 23        }
 24        public class SeqQueue<T> : IQueue<T>
 25        {  
 26            //循环顺序队列的容量
 27            private int maxsize;
 28            //存储顺序队列中的值
 29            private T[] data;
 30            //队头
 31            private int front;
 32            //队尾
 33            private int rear;
 34
 35            //索引器
 36            public T this[int index]
 37            {
 38                get
 39                { 
 40                   return data[index];
 41                }
 42                set
 43                {
 44                    data[index] = value;
 45                }
 46            }
 47            //容量属性
 48            public int Maxsize
 49            {
 50                get 
 51                {
 52                    return maxsize;
 53                }
 54                set
 55                {
 56                    maxsize = value;
 57                }
 58            }
 59            //队头属性
 60            public int Front
 61            {
 62                get
 63                {
 64                    return front;
 65                }
 66                set
 67                {
 68                    front = value;
 69                }
 70            }
 71            //队尾属性
 72            public int Rear
 73            {
 74                get
 75                {
 76                    return rear;
 77                }
 78                set
 79                {
 80                    rear = value;
 81                }
 82            }
 83            //构造器
 84            public SeqQueue(int size)
 85            { 
 86               data=new T[size];
 87               maxsize = size;
 88               front = rear = -1;
 89            }
 90            //求长度
 91            public int GetLength()
 92            {
 93                return (rear - front + maxsize) % maxsize;
 94            }
 95            //清空
 96            public void Clear()
 97            {
 98                front = rear = -1;
 99            }
            //判断队列是否为空
            public bool IsEmpty()
            {
                if (front == rear)
                {
                    return true;
                }
                else
                {
                    return false;
                }
    
            }
            //判断队列是否已满
            public bool IsFull()
            {
                if ((rear + 1) % maxsize == front)
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            //入队
            public void In(T item)
            {
                if (IsFull())
                {
                    Console.WriteLine("队列已满！");
                    return;
                }
                data[++rear] = item;
            }
            //出队
            public T Out()
            { 
                T tmp=default(T);
                if (IsEmpty())
                {
                    Console.WriteLine("队列是空的！");
                    return tmp;
                }
                tmp=data[++front];
                return tmp;
            }

            //获取队头元素
            public T GetFront()
            {
                if (IsEmpty())
                {
                    Console.WriteLine("队列是空的！");
                    return default(T);
                }
                return data[front+1];
            }
        }
        static void Main(string[] args)
        {
            SeqQueue<int> queue = new SeqQueue<int>(10);
            int[] str = new int[] {1,2,3,4,5,6};
            for (int i = 0; i < str.Length; i++)
            {
                queue.In(str[i]);  
            }
            Console.WriteLine(queue.GetFront());
        }
    }
}