数据结构之---C语言实现链式队列

//链式队列的存储
//杨鑫
#include <stdio.h>
#include <stdlib.h>
typedef int QElemType;

//定义节点
typedef struct QNode
{
		QElemType data;
		struct QNode *next;
}QNode, *QueuePtr;

//定义指针
typedef struct
{
	QueuePtr front;
	QueuePtr rear;
}LinkQueue;

//插入元素e进入队列
void en_Queue(LinkQueue *q, QElemType e)
{
	QueuePtr temp = (QueuePtr)malloc(sizeof(QNode));
	if(temp)
	{
		temp->data = e;
		temp->next = NULL;
		q->rear->next = temp;
		q->rear = temp;
	}
}

//初始化队列
void init_Queue(LinkQueue *q)
{
		q->front = q->rear = (QNode *)malloc(sizeof(QNode));
		q->front->next = NULL;
}

//创建队列
void create_Queue(LinkQueue *q)
{
		int n = 0;
		init_Queue(q);
		printf("请输入要进入队列的元素，以0结束!\n");
		while(scanf("%d", &n))
		{
			if(n == 0)
					break;
			en_Queue(q, n);
		}
}

//e元素出队
void de_Queue(LinkQueue *q, QElemType *e)
{
	if(q->front == q->rear)
			return;
	QueuePtr temp = q->front->next;
	if(q->front->next == q->rear)
			q->rear = q->front;
	*e = temp->data;
	q->front->next = temp->next;
	free(temp);
}

//判断队列是否为空
int is_Empty(LinkQueue *q)
{
	if(q->front == q->rear)
			return 1;
	return 0;
}

//返回队列
int getlength_Queue(LinkQueue *q)
{
	QueuePtr temp = q->front;
	int i = 0;
	while(temp != q->rear)
	{
		++i;
		temp = temp->next;
	}
	return i;
}

//清空队列
void clear(LinkQueue *q)
{
	QueuePtr temp = q->front->next;
	while(temp)
	{
		QueuePtr tp = temp;
		temp = temp->next;
		free(tp);
	}
	temp = q->front;
	q->front = q->rear = NULL;
	free(temp);
}

//打印队列元素
void print_Queue(LinkQueue *q)
{
		if(q->front == q->rear)
				return;
		QueuePtr temp = q->front->next;
		while(temp != q->rear)
		{
			printf("%d ", temp->data);
			temp = temp->next;
		}
		printf("%d", temp->data);
		printf("\n");
}

//第一个数据出队
void top_Queue(LinkQueue *q, QElemType *e)
{
	if(q->front == q->rear)
			return;
	*e = q->front->next->data;
}

int main()
{
		int i = 0, k = 0, top = 0;
		int len;
		LinkQueue q;
		create_Queue(&q);
		top_Queue(&q, &top);
		printf("队头的元素为:%d\n", top);
		len = getlength_Queue(&q);
		printf("遍历队中的所有元素:\n");
		for(i = 0; i < len; i++)
		{
			de_Queue(&q, &k);
			printf("%d ", k);
		}
		printf("\n");
		clear(&q);
		return 0;
}