队列的实现

main.c文件

#include"Queue.h"

int main()
{
	QueueTest();
	system("pause");
	return 0;
}

Queue.h文件

#pragma once

#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
#include<assert.h>

typedef int QUDataType;

typedef struct QueueNode
{
	QUDataType _data;
	struct QueueNode *_next;
}QueueNode;

typedef struct Queue
{
	QueueNode *_front;
	QueueNode *_rear;
}Queue;

void QueueInit(Queue *q);
void QueueDestory(Queue *q);
void QueuePush(Queue *q, QUDataType x);
void QueuePop(Queue *q);
int QueueSize(Queue *q);
int QueueEmpty(Queue *q);
QUDataType QueueFront(Queue *q);
QUDataType QueueRear(Queue *q);
void QueueTest();

Queue.c文件

#include"Queue.h"

void QueueInit(Queue *q)
{
	assert(q);

	q->_front = q->_rear = NULL;
}

void QueueDestory(Queue *q)
{
	assert(q);

	QueueNode * cur = q->_front;
	while (cur)
	{
		QueueNode * next = cur->_next;
		free(cur);
		cur = next;
	}
}

void QueuePush(Queue *q, QUDataType x)
{
	assert(q);
	
	//申请结点
	QueueNode *newNode = (QueueNode*)malloc(sizeof(QueueNode));
	newNode->_data = x;
	//连接到队尾1.空队列2.有数据
	if (q->_front == NULL)
	{
		q->_front = q->_rear = newNode;
		q->_rear->_next = NULL;
	}
	else
	{
		q->_rear->_next = newNode;
		q->_rear = q->_rear->_next;
		q->_rear->_next = NULL;
	}
}

void QueuePop(Queue *q)
{
	assert(q);

	//空队列不能删除
	if(q->_front)
	{
		QueueNode *next = q->_front->_next;
		free(q->_front);
		q->_front = next;
	}
}

int QueueSize(Queue *q)
{
	assert(q);

	QueueNode *cur = q->_front;
	int size = 0;
	while (cur)
	{
		size++;
		cur = cur->_next;
	}
	return size;
}

int QueueEmpty(Queue *q)
{
	assert(q);

	if (q->_front == NULL)
	{
		return 0;
	}
	else
	{
		return 1;
	}
}

QUDataType QueueFront(Queue *q)
{
	assert(q);

	return q->_front->_data;
}

QUDataType QueueRear(Queue *q)
{
	assert(q);

	return q->_rear->_data;
}

void QueueTest()
{
	Queue qu;
	QueueInit(&qu);
	QueuePush(&qu, 1);
	QueuePush(&qu, 2);
	QueuePush(&qu, 3);
	QueuePush(&qu, 4);
	QueuePush(&qu, 5);
	printf("Empty:%d\n", QueueEmpty(&qu));
	printf("Size:%d\n", QueueSize(&qu));
	while (qu._front!=NULL)
	{
		printf("Front=%d\n", QueueFront(&qu));
		QueuePop(&qu);
	}
	printf("Empty:%d\n", QueueEmpty(&qu));
	printf("Size:%d\n", QueueSize(&qu));
	QueueDestory(&qu);
}