这个链队列不知道哪里出错了啊

[Rookie_Allen]

#include<stdio.h>
#include<stdlib.h>
typedef char datatype;
typedef struct node
{
datatype data;
struct node *next;
}linklist;

typedef struct
{
linklist *front,*rear;
}linkqueue;

void SETNULL(linkqueue *q)//置队列空
{
q=(linkqueue *)malloc(sizeof(linkqueue));
q->front->next=0;
q->rear=q->front;
}

int EMPTY(linkqueue *q)//判队列空
{
if(q->front==q->rear)return 1;
else
return 0;
}

void ENQUEUE(linkqueue *q,datatype x)//入队列
{
q->rear->next=(linkqueue *)malloc(sizeof(linkqueue));
q->rear=q->rear->next;
q->rear->data=x;
q->rear->next=0;
}

datatype DEQUEUE(linkqueue *q)//出队列
{
linklist *s;
if(EMPTY(q))
{printf("queue is empty.\n");return 0;}
else
{
s=q->front;
q->front=q->front->next;
free(s);
return q->front->data;
}
}

datatype FRONT(linkqueue *q)
{
if(EMPTY(q))
{printf("queue is empty.\n");return 0;}
else
return q->front->next->data;
}

void main()
{
linkqueue *q;
datatype x=1,y=2,z=3;
SETNULL(q);
ENQUEUE(q,x);
printf("%d enqueue\n",q->rear->data);
ENQUEUE(q,y);
printf("%d enqueue\n",q->rear->data);
ENQUEUE(q,z);
printf("%d enqueue\n",q->rear->data);
x=DEQUEUE(q);
printf("%d dequeue\n",q->front->data);
y=DEQUEUE(q);
printf("%d dequeue\n",q->front->data);
z=DEQUEUE(q);
printf("%d dequeue\n",q->front->data);
}

[cwc270]

问题比较多

#include <stdio.h> 
#include <stdlib.h> 
typedef char datatype; 
typedef struct node 
{ 
	datatype data; 
	struct node *next; 
}linklist; 

typedef struct 
{ 
	linklist *front,*rear; 
}linkqueue; 

void SETNULL(linkqueue *&q)//置队列空 
{ 
	q=(linkqueue *)malloc(sizeof(linkqueue)); 
	q->front=NULL; 
	q->rear=NULL; 
} 

int EMPTY(linkqueue *q)//判队列空 
{ 
	if(q==NULL || q->front==NULL)
		return 1; 
	else 
		return 0; 
} 

void ENQUEUE(linkqueue *q,datatype x)//入队列 
{ 
	if (q== NULL)
		return;

	linklist *s = (linklist *)malloc(sizeof(linklist));
	s->next = NULL;
	s->data = x;
	if (q->rear == NULL)
	{
		q->front = s;
		q->rear = s;
	}
	else
	{
		q->rear->next = s; 
		q->rear = s; 
	}
} 

datatype DEQUEUE(linkqueue *q)//出队列 
{ 
	linklist *s; 
	if(EMPTY(q)) 
	{
		printf("queue is empty.\n");
		return 0;
	} 
	else 
	{ 
		s=q->front; 
		datatype tmp = s->data;

		q->front=s->next; 
		free(s); 

		return tmp; 
	} 
} 

datatype FRONT(linkqueue *q) 
{ 
	if(EMPTY(q)) 
	{
		printf("queue is empty.\n");
		return 0;
	} 
	else 
		return q->front->data; 
} 
void main() 
{ 
	linkqueue *q; 
	datatype x=1,y=2,z=3; 
	SETNULL(q); 
	ENQUEUE(q,x); 
	printf("%d enqueue\n",q->rear->data); 
	ENQUEUE(q,y); 
	printf("%d enqueue\n",q->rear->data); 
	ENQUEUE(q,z); 
	printf("%d enqueue\n",q->rear->data); 
	x=DEQUEUE(q); 
	printf("%d dequeue\n",x); 
	y=DEQUEUE(q); 
	printf("%d dequeue\n",y); 
	z=DEQUEUE(q); 
	printf("%d dequeue\n",z); 
	free(q);
}

[Rookie_Allen]

谢谢CWC270,经常得到你的帮助!