C++ 链队列和循环队列基本操作

来源：互联网发布：软件可靠性测试分析编辑：程序博客网时间：2024/06/15 17:01

一：目的

1. 用C++实现链队列的基本操作

2. 用C++实现循环队列的基本操作

二：链队列的实现

1. 定义数据结构和类，书写在Queue.h中

# include <iostream>using namespace std;typedef int ElemType;typedef struct QNode{ElemType data;QNode *next;}QNode, *QueuePtr;      //节点//单链队列typedef struct{QueuePtr front;     //队头指针QueuePtr rear;//队尾指针}LinkQueue; class MyLinkQueue { public: void InitQueue();//初始化队列 void DestroyQueue();//销毁队列 void ClearQueue();//清空队列 bool QueueEmpty();//队列是否为空 int QueueLength();//队列长度 void Enqueue(ElemType val);//在队尾插入数据 void DeQueue(ElemType & val);//删除队头 void Print();//从头到尾打印 private: LinkQueue q; };

2. 具体实现代码在Queue.cpp中

#include "Queue.h"//初始化队列void MyLinkQueue::InitQueue(){q.front = q.rear = (QueuePtr)malloc(sizeof(QNode));if(!q.front){//如果分配失败cout <<"初始化失败"<<endl;return;}q.front->next = NULL;}//销毁队列void MyLinkQueue::DestroyQueue(){while(q.front){q.rear = q.front->next;free(q.front);q.front = q.rear;}}//在队尾插入数据void MyLinkQueue::Enqueue(ElemType val){QueuePtr ptr = (QueuePtr)malloc(sizeof(QNode));if(!ptr){//如果分配失败cout << "节点分配失败" << endl;return;}ptr->data = val;ptr->next = NULL;q.rear->next = ptr;q.rear = ptr;}//删除队头，并返回当前队头的值void MyLinkQueue::DeQueue(ElemType & val){if(q.front == q.rear){val = -1;return;}    QueuePtr p;    val = q.front->next->data;    if(q.front->next == q.rear){//队列只有一个元素        p = q.rear;        q.rear = q.front;        q.front->next = NULL;    }else{        p = q.front->next;        q.front->next = p->next;        p->next = NULL;    }        free(p);}//打印void MyLinkQueue::Print(){if(q.front == q.rear){cout<< "队列为空" << endl;return;}QueuePtr ptr = q.front->next;while(ptr!=q.rear){cout<<ptr->data<<endl;ptr = ptr->next;}cout<<ptr->data<<endl;}//清空队列void MyLinkQueue::ClearQueue(){DestroyQueue();InitQueue();}//队列是否为空bool MyLinkQueue::QueueEmpty(){if(q.front == q.rear)return true;elsereturn false;}//队列长度int MyLinkQueue:: QueueLength(){if(q.front == q.rear)return 0;QueuePtr ptr = q.front;int index = 0;do{index++;ptr = ptr->next;}while(ptr!=q.rear);return index;}

3.简单测试如下

MyLinkQueue q;bool flag = q.QueueEmpty();q.InitQueue();q.Enqueue(1);q.Enqueue(2);q.Enqueue(3);q.Enqueue(4);q.Enqueue(5);q.Enqueue(6);q.Enqueue(7);int len = q.QueueLength();q.Print();int val;q.DeQueue(val);q.DeQueue(val);cout <<"取出两个队头后"<<endl;q.Print();q.ClearQueue();q.Print();q.Enqueue(1);q.Enqueue(2);q.Enqueue(3);q.Enqueue(4);q.Print();

三：循环队列的实现

1. 定义数据结构和类，书写在Queue.h中

# include <iostream>using namespace std;#define MAX_QUEUE_SIZE 100typedef int ElemType;typedef struct QNode{ElemType data;QNode *next;}QNode, *QueuePtr;      //节点//循环队列 typedef struct{ElemType *base;int front;int rear;}SqQueue;class CircularQueue { public: void InitQueue();//初始化队列 void DestroyQueue();//销毁队列 void ClearQueue();//清空队列 bool QueueEmpty();//队列是否为空 int QueueLength();//队列长度 void Enqueue(ElemType val);//在队尾插入数据 void DeQueue(ElemType & val);//删除队头 void Print();//从头到尾打印 private: SqQueue q; };

2.具体实现在Circular_Queue.cpp中

#include "Queue.h"//初始化队列void CircularQueue::InitQueue(){q.base = (ElemType *)malloc(sizeof(ElemType) * MAX_QUEUE_SIZE);if(!q.base){//如果分配失败cout <<"初始化失败"<<endl;return;}q.front = q.rear = 0;}//销毁队列void CircularQueue::DestroyQueue(){free (q.base);q.front = q.rear = 0;}//在队尾插入数据void CircularQueue::Enqueue(ElemType val){if((q.rear + 1)%MAX_QUEUE_SIZE == q.front){cout << "队列已满！" << endl;return;}q.base[q.rear] = val;q.rear = (q.rear+1)%MAX_QUEUE_SIZE;return;}//删除队头，并返回当前队头的值void CircularQueue::DeQueue(ElemType & val){if(q.front == q.rear){cout<<"队列为空！"<<endl;return;}val = q.base[q.front];q.front = (q.front+1)%MAX_QUEUE_SIZE;return;}//打印void CircularQueue::Print(){if(q.front == q.rear){cout<< "队列为空" << endl;return;}for(int i = q.front; i < q.rear;i++)cout<< q.base[i]<<endl;return;}//清空队列void CircularQueue::ClearQueue(){DestroyQueue();InitQueue();}//队列是否为空bool CircularQueue::QueueEmpty(){if(q.front == q.rear)return true;elsereturn false;}//队列长度int CircularQueue:: QueueLength(){return (q.rear - q.front + MAX_QUEUE_SIZE) % MAX_QUEUE_SIZE;}

3. 测试同上，只需要将MyLinkQueue改为CircularQueue即可

阅读全文

0 0