程序猿面试宝典（第三版）--队列的建立，測长，打印，入队，出队

港控/mmm° 2022-03-30 13:38 163阅读 0赞

编程实现队列的建立，測长，打印，入队，出队。

#include<iostream>
    #include<stdio.h>
    #include<string.h>
    #include<conio.h>
    using namespace std;
    
    typedef struct student
    {
    	int data;
    	struct student *next;
    }node;
    
    typedef struct linkqueue
    {
    	node *front;
    	node *rear;
    }queue;
    
    queue *create()
    {
    	queue *q;
    	q=new queue;
    	q->front=NULL;
    	q->rear=NULL;
    	return q;
    }
    int length(queue *HQ)
    {
    	if(HQ==NULL||HQ->rear==NULL)
    	{
    		cout<<"队列的长度为：0"<<endl;//空队列
    		return 0;
    	}
    		
    	int i=0;
    	node *p;
    	p=HQ->front;
    	while(p!=NULL)
    	{
    		p=p->next;
    		i++;
    	}
    	cout<<"队列的长度为："<<i<<endl;//更新队列的长度
    	return i;
    }
    
    void print(queue *HQ)
    {
    	node *p;
    	p=HQ->front;
    	cout<<"队列中的元素：";//
    	if(p==NULL)
    	{
    		cout<<"空队列"<<endl;//
    		return ;
    	}
    	while(p!=NULL)
    	{
    		cout<<p->data<<" ";//打印
    		p=p->next;
    	}
    	cout<<endl;
    }
    
    queue *insert(queue *HQ,int num)
    {
    	node *s;
    
    	s=(node *)malloc(sizeof(node));
    	s->data=num;
    	s->next=NULL;
    	cout<<s->data<<"入队。";//
    	if(HQ->front==NULL)//if(HQ->rear==NULL)//在空队列中进行元素入队操作
    	{
    		HQ->front=s;
    		HQ->rear=s;
    	}
    	else
    	{
    		HQ->rear->next=s;
    		HQ->rear=s;
    	}
    	cout<<endl;
    	return HQ;
    }
    
    queue *dele(queue *HQ)
    {
    	node *p;int x;
    	cout<<"出队：";//
    	if(HQ->front==NULL)//HQ->reat==NULL//在空队列中进行元素出队操作
    		printf("空队列");
    	else
    	{
    		x=HQ->front->data;
    		p=HQ->front;
    		cout<<x;
    		if(HQ->front==HQ->rear)//队列中仅仅有一个元素
    		{
    			HQ->front=NULL;
    			HQ->rear=NULL;
    		}
    		else
    		{
    			HQ->front=HQ->front->next;
    		}
    		free(p);	
    	}
    	cout<<endl;
    	return HQ;
    }
    
    void main()
    {
    	queue *HQ;
    	HQ=create();
    	HQ=dele(HQ);//对空队列进行出队操作
    	int n;
    	HQ=insert(HQ,10);//入队
    	HQ=insert(HQ,2);
    	HQ=insert(HQ,3);
    	HQ=insert(HQ,4);
    	HQ=insert(HQ,5);
    	HQ=insert(HQ,6);
    	n=length(HQ);
    	print(HQ);
    	HQ=dele(HQ);//出队
    	HQ=dele(HQ);
    	HQ=dele(HQ);
    	HQ=dele(HQ);
    	HQ=dele(HQ);
    	HQ=dele(HQ);
    	n=length(HQ);
    	print(HQ);
    	HQ=dele(HQ);//对空队列进行出队操作
    	n=length(HQ);
    	print(HQ);
    }

执行结果：  
![SouthEast][]

[SouthEast]: /images/20220330/28dc7e5f8e704a49829cd3f25bc9cc8b.png