关于链式结构的队列的一个问题，请大家指导。。
添加if(pFirst->front == pFirst->rear)
{
puts("queue is empty!!");
exit(0);
}出队失败。。，删除后出队成功
程序代码：#include <stdio.h>
#include <stdlib.h>
typedef struct NQUEUE
{
int data;
struct NQUEUE *next;
}nQueue;
typedef struct LQUEUE
{
nQueue *front;
nQueue *rear;
}lQueue;
void display(lQueue *);
void init(lQueue *);
void enQueue(lQueue *, int);
void deQueue(lQueue *);
int main(void)
{
lQueue *pFirst = (lQueue *)malloc(sizeof(lQueue));
int data = 0;
int i = 0;
init(pFirst);
for( i = 1; i < 8; i++ )
{
enQueue(pFirst, i);
}
display(pFirst);
deQueue(pFirst);
deQueue(pFirst);
puts("");
display(pFirst);
return 0;
}
void display(lQueue *pFirst)
{
nQueue *tmp = pFirst->front->next;
while(tmp)
{
printf("%3d", tmp->data);
tmp = tmp->next;
}
}
void init(lQueue *pFirst)
{
pFirst->front = pFirst->rear = (nQueue *)malloc(sizeof(nQueue));
pFirst->front->next = NULL;
pFirst->front->data = 0;
}
void enQueue(lQueue *pFirst, int e)
{
nQueue *tmp = (nQueue *)malloc(sizeof(nQueue));
tmp->data = e;
tmp->next = NULL;
pFirst->rear->next = tmp;
pFirst->rear = tmp;
}
void deQueue(lQueue *pFirst)
{
nQueue *tmp = NULL;
if(pFirst->front == pFirst->rear)//问题所在。。。
{
puts("queue is empty!!");
exit(0);
}
tmp = pFirst->front->next;
pFirst->front->next = tmp->next;
if(tmp == pFirst->rear);
{
pFirst->rear = pFirst->front;
}
free(tmp);
tmp = NULL;
}
~~~~~~~~
