C#数据结构和算法学习系列七----队列、队列的实现和应用

时间:2022-04-07 10:20:44


     队列是一种把数据从表的末端放入并在表的前端移除的数据结构。队列会按照数据项出现的顺序来存储它们。队列是先进先出(FIFO)数据结构的实例。队列用来对提交给操作系统或打印池的任务进行排序,而模拟应用程序则用队列对用户等待队列进行模拟。队列包含两种主要的操作。一个是给队列添加新的数据项,另一个则是把数据项从队列中移除。添加新数据项的操作被称为是Enqueue,而从队列中移除数据项的操作则被称为是Dequeue。Enqueue 操作会在队列的末尾添加一个数据项,而Dequeue 操作则会从队列的
前端(或开始处)移除一个数据项。

(1).Queue类。下面这个Queue 类的实现包含EnQueue 方法、DeQueue 方法、ClearQueue 方法(清除队列)、Peek 方法以及Count 方法,而且还有一个用于此类的默认构造器。

public class CQueue
{
private ArrayList pqueue;
public CQueue()
{
pqueue = new ArrayList();
}
public void EnQueue(object item)
{
pqueue.Add(item);
}
public void DeQueue()
{
pqueue.RemoveAt(0);
}
public object Peek()
{
return pqueue[0];
}
public void ClearQueue()
{
pqueue.Clear();
}
public int Count()
{
return pqueue.Count;
}
}

(2).Queue的应用

     1.几种初始化方式

        Queue myQueue = new Queue(100);

        Queue myQueue = new Queue(32, 3);

        Queue<int> numbers = new Queue<int>();

      2.实例应用

using System;
using System.Collections;
using System.IO ;
namespace csqueue
{
public struct Dancer
{
public string name;
public string sex;
public void GetName(string n)
{
name = n;
}
public override string ToString()
{
return name;
}
}
class Class1
{
static void newDancers(Queue male, Queue female)
{
Dancer m, w;
m = new Dancer();
w = new Dancer();
if (male.Count > 0 && female.Count > 0)
{
m.GetName(male.Dequeue().ToString());
w.GetName(female.Dequeue().ToString());
}
else if ((male.Count > 0) && (female.Count == 0))
Console.WriteLine("Waiting on a female dancer.");
else if ((female.Count > 0) && (male.Count == 0))
Console.WriteLine("Waiting on a male dancer.");
}
static void headOfLine(Queue male, Queue female)
{
Dancer w, m;
m = new Dancer();
w = new Dancer();
if (male.Count > 0)
m.GetName(male.Peek().ToString());
if (female.Count > 0)
w.GetName(female.Peek().ToString());
if (m.name != " " && w.name != "")
Console.WriteLine("Next in line are: " + m.name + "\t" + w.name);
else
if (m.name != "") //!=
Console.WriteLine("Next in line is: " + m.name);
else
Console.WriteLine("Next in line is: " + w.name);
}
static void startDancing(Queue male, Queue female)
{
Dancer m, w;
m = new Dancer();
w = new Dancer();
Console.WriteLine("Dance partners are: ");
Console.WriteLine();
for (int count = 0; count <= 3; count++)
{
m.GetName(male.Dequeue().ToString());
w.GetName(female.Dequeue().ToString());
Console.WriteLine(w.name + "\t" + m.name);
}
}
static void formLines(Queue male, Queue female)
{
Dancer d = new Dancer();
StreamReader inFile;
inFile = File.OpenText(@"c:\dancers.dat");
string line;
while (inFile.Peek() != -1)
{
line = inFile.ReadLine();
d.sex = line.Substring(0, 1);
d.name = line.Substring(2, line.Length - 2);
if (d.sex == "M")
male.Enqueue(d);
else
female.Enqueue(d);
}
}
static void Main(string[] args)
{
Queue males = new Queue();
Queue females = new Queue();
formLines(males, females);
startDancing(males, females);
if (males.Count > 0 || females.Count > 0)
headOfLine(males, females);
newDancers(males, females);
if (males.Count > 0 || females.Count > 0)
headOfLine(males, females);
newDancers(males, females);
Console.Write(" press enter");
Console.Read();
}
}