循环队列

#include "stdafx.h"

#include <iostream>
using namespace std;

typedef int DataType;
#define MAXSIZE 5

typedef struct{
	DataType *base;
	int front;
	int rear;
}CircleQueue;

CircleQueue *init(CircleQueue *queue)
{
	queue->base = (DataType*)malloc(MAXSIZE*sizeof(DataType));
	if(!queue) exit(0);
	queue->rear = queue->front =0;
	return queue;
}

int getLength(CircleQueue *queue)
{
	return (queue->rear - queue->front +MAXSIZE)%MAXSIZE;
}

void inQueue(CircleQueue *queue,DataType e)
{
	if((queue->rear+1)%MAXSIZE ==queue->front)
	{
		cout<<"the queue is full"<<endl;
		exit(0);
	}else
	{
		queue->base[queue->rear] = e;
		queue->rear = (queue->rear+1)%MAXSIZE;
	}
}

void outQueue(CircleQueue *queue)
{
	if(queue->front == queue->rear)
	{
		cout<<"the queue is empty"<<endl;
		exit(0);
	}else
	{
		cout<<"the out element is :"<<queue->base[queue->front];
		queue->front= (queue->front+1)%MAXSIZE;
	}
}

void main()
{
	CircleQueue Q;
	Q = *init(&Q);
	cout<<"after init queue length:"<<getLength(&Q)<<endl;
	inQueue(&Q,1);
	cout<<"after input queue length:"<<getLength(&Q)<<endl;
	inQueue(&Q,2);
	cout<<"after input queue length:"<<getLength(&Q)<<endl;
	inQueue(&Q,3);
	cout<<"after input queue length:"<<getLength(&Q)<<endl;
	inQueue(&Q,4);
	cout<<"after input queue length:"<<getLength(&Q)<<endl;
	outQueue(&Q);
	cout<<"after output queue length:"<<getLength(&Q)<<endl;
	inQueue(&Q,5);
	cout<<"after input queue length:"<<getLength(&Q)<<endl;
	inQueue(&Q,6);
	cout<<"after input queue length:"<<getLength(&Q)<<endl;

	

}