利用 C++ 单向链表实现队列

#pragma once

#include "stdio.h"
//利用链表来实现队列，先进先出

class queue
{
public:
queue(void);
queue(int value);
~queue(void);
private:
int m_value;
queue* m_pnext;
public:
void push(int value);
bool pop(int *value);
bool top(int *value);
bool empty();
int size();
void output();
void destroy();
};

#include "stdafx.h"
#include "queue.h"

//构造一个空的队列头指针
queue::queue(void)
{
m_value = 0x00;
m_pnext = NULL;
}

//构建一个队列结点
queue::queue(int value)
{
m_value = value;
m_pnext = NULL;
}

//输出被删除掉的结点
queue::~queue(void)
{
printf("destroy node its value=%d\n", m_value);
}

//元素入队列
void queue::push(int value)
{
queue *pnode = this;
while(pnode->m_pnext != NULL)
{
pnode = pnode->m_pnext;
}
queue *newnode = new queue(value);
pnode->m_pnext = newnode;
m_value++;
}

//元素出队列
bool queue::pop(int *value)
{
bool result = false;
if (m_pnext != NULL)
{
*value = m_pnext->m_value;
m_pnext = m_pnext->m_pnext;
result = true;
m_value--;
}
return result;
}

//得到队列顶部的元素
bool queue::top(int *value)
{
bool result = false;
if (m_pnext != NULL)
{
*value = m_pnext->m_value;
result = true;
}
return result;
}

//判断队列是否为空
bool queue::empty()
{
bool result = false;
if (m_pnext == NULL)
{
result = true;
}
return result;
}

//得到队列大小
int queue::size()
{
return m_value;
}

//输出队列中的元素
void queue::output()
{
queue* pnode = this;
while(pnode->m_pnext != NULL)
{
printf("index=%d\n", pnode->m_pnext->m_value);
pnode = pnode->m_pnext;

}
}

//销毁队列
void queue::destroy()
{
while(m_pnext != NULL)
{
queue* pnode = m_pnext;
m_pnext = m_pnext->m_pnext;
delete pnode;
}
}

// myqueue.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "queue.h"

int _tmain(int argc, _TCHAR* argv[])
{
queue myqueue;
for(int i=0; i<10; i++)
{
myqueue.push(i * 10);
}

myqueue.output();
printf("queue size=%d\n", myqueue.size());

if (myqueue.empty())
{
printf("queue is empty\n");
}
else
{
printf("queue is not empty\n");
}

myqueue.destroy();

int value = 0;
for(int i=0; i<10; i++)
{
if (myqueue.pop(&value))
{
printf("pop value=%d successfully\n", value);
}
else
{
printf("pop unsuccessfully\n");
}
}

printf("queue size=%d\n", myqueue.size());

if (myqueue.empty())
{
printf("queue is empty\n");
}
else
{
printf("queue is not empty\n");
}

getchar();
return 0;
}