循环队列的相关操作（顺序结构）

typedef int Elemtype
typedef struct
{
Elemtype data[MAXSIZE];
int front;
int rear;
}SqQueue;

Status InitQueue(SqQueue *Q)
{
Q->front=0;
Q->rear=0;
return OK;
}

int QueueLength(SqQueue Q)
{
return (Q.rear-Q.front+MAXSIZE)%MAXSIZE;
}

Status EnQueue(SqQueue *Q,Elemtype e)
{
if((Q->rear+1)%MAXSIZE==Q->front) return ERROR;//队列满的判断
Q->data[Q->rear]=e;
Q->rear=(Q->rear+1)%MAXSIZE;

return OK;
}

Status DeQueue(SqQueue *Q,Elemtype &e)
{
if(Q->front==Q->rear) return ERROR;//队列空的判断
e=Q->data[Q->front];
Q->front=(Q->front+1)%MAXSIZE;

return OK;
}