循环队列
代码如下:
#include "pch.h"
#include <iostream>
using namespace std;
#define MAXSIZE 5
struct SqQueue
{
char* Base;
int front;
int rear;
};
//初始化循环队列
int initqueue(SqQueue &q)
{
q.Base = new char[MAXSIZE];
if (!q.Base)
{
cout << "内存空间分配失败!" << endl;
return 0;
}
q.front = q.rear = 0;
return 1;
}
//求循环队列的长度
int getqueuelength(SqQueue q)
{
return (q.rear - q.front + MAXSIZE) % MAXSIZE;
}
//求循环队列的头元素
char getqueuehead(SqQueue q)
{
return q.Base[q.front]; //q.front 是下标位置
}
//循环队列的入队
int insertqueue(SqQueue &q, char e)
{
if ((q.rear+1)%MAXSIZE==q.front)//这样队列就满了
{
cout << "队列已满,无法继续插入队列!" << endl;
return 0;
}
q.Base[q.rear] = e;
q.rear = (q.rear + 1) % MAXSIZE;
cout << "入队列成功!" << endl;
return 1;
}
//循环队列的出队列
int outputqueue(SqQueue &q, char e)
{
if (q.rear==q.front)
{
cout << "队列为空,无法出队列!" << endl;
return 0;
}
e=q.Base[q.front];
q.front = (q.front + 1) % MAXSIZE;
cout << "出队列成功!" << endl;
return 1;
}
int main()
{
SqQueue q;
initqueue(q);
insertqueue(q, 'a');
insertqueue(q, 'b');
insertqueue(q, 'c');
cout << getqueuehead(q) << endl;;
char c='a';
outputqueue(q,c);
cout << getqueuehead(q) << endl;
outputqueue(q, c);
cout << getqueuehead(q) << endl;
cout << "循环队列的长度为:" << getqueuelength(q) << endl;
return 0;
}
结果为:
链队列
代码如下:
#include "pch.h"
#include <iostream>
using namespace std;
//链队列
typedef struct qnode
{
char data;
qnode *next;
}*queueper;
//头指针和尾指针
struct linkqueue
{
queueper front; //队列的尾指针
queueper rear; //队列的头指针
};
//初始化队列
int initlinkqueue(linkqueue &q)
{
//创建新节点设置为头,队尾队头志向该节点
q.front = q.rear = new qnode;
q.rear->next = NULL;//头结点指针域设置为空
return 0;
}
//获取队列的头元素
char getqueueHead(linkqueue q)
{
if (q.front!=q.rear)
{
return q.front->next->data;
}
}
//链队列入队列
int insertelem(linkqueue &q,char e)
{
queueper p;
p = new qnode;
p->data = e;
p->next = NULL;
q.rear->next = p; //将新节点插入到队列的尾部(后插法)
q.rear = p; //尾指针指向尾结点
cout << "队列入队成功!" << endl;
return 0;
}
//链队列出队列
int outputqueue(linkqueue &q, char &e)
{
queueper p;
if (q.rear==q.front)
{
cout << "队列为空,无法出队列!" << endl;
return 0;
}
p = q.front->next; //指向队头元素
e = p->data; //得到队头元素的数据域
q.front->next = p->next;//修改头指针
if (q.front==p)
{
q.rear = q.front;
}
delete p;
cout << "出队列成功!" << endl;
return 1;
}
int main()
{
linkqueue q;
initlinkqueue(q);
insertelem(q, 'a');
insertelem(q, 'b');
insertelem(q, 'c');
insertelem(q, 'd');
cout << "队列的头元素为:" << getqueueHead(q) << endl;
char e = 'a';
outputqueue(q, e);
cout << "队列的头元素为:" << getqueueHead(q) << endl;
outputqueue(q, e);
cout << "队列的头元素为:" << getqueueHead(q) << endl;
return 0;
结果为: