C++primer plus第六版课后编程题答案12.6

myQueue,cpp不变

main126.cpp

#include <iostream>
#include "myQueue.cpp"
#include <cstdlib>
#include <ctime>
using namespace std;
static const int MIN_PER_HR=60;
bool newCustomer(double x)//每隔x次，rand()/RAND_max会有一次值<1
{
return rand()*x/RAND_MAX<1;
}
void main126()
{
srand(time(0));//初始化rand();
cout<<"Case Study:Bank of Heather Automatic Teller"<<endl;
cout<<"Enter maximum size of queue:";
int qs;
cin>>qs;
Queue line(qs);
Queue line2(qs);//视为同样大小的队列

cout<<"Enter the number of simulation hours:";
int hours;
cin>>hours;
long cyclelimit=MIN_PER_HR*hours;//循环的分钟数

cout<<"Enter the average number of customers per hour:";//一个小时来的人数
double perhour;
cin>>perhour;
double min_per_cust;
min_per_cust=MIN_PER_HR/perhour;//平均多少分钟来一个人

Item temp;
long turnaways=0;
long customers=0;
//long served=0;
long served=0;
long sum_line=0;
int wait_time=0;
int wait_time2=0;//等待时间要+1个
long line_wait=0;

for(int cycle=0;cycle<cyclelimit;cycle++)//cycle每循环一次，代表过了一分钟
{
//line.s();
if(newCustomer(min_per_cust))
{
if(line.isFull()&&line2.isFull())//当两个队列都满了的时候才拒绝服务
turnaways++;//拒绝服务？？？//恩,应该就是拒绝服务的人数
else
{
customers++;//队列人数//应该是顾客人数+1而不是队列人数+1
temp.set(cycle);//cycle是到达时间
if(line.queuecount()>=line2.queuecount())
line2.enQueue(temp);
else
line.enQueue(temp);//这里的items++才是队列人数+1
//cout<<"after insert "<<line;//test

}

}
if(wait_time<=0&&!line.isEmpty())//队列1中有用户处理完了业务
{
line.deQueue(temp);
//cout<<"after the delete"<<line;//test
wait_time=temp.ptime();//wait_time是该客户处理业务所用时间
line_wait+=cycle-temp.when();//cycle-temp.when();是该客户一共在队列中等了多久
//一开始wait_time初始化是0，然后进入这里之后，又重新设置了使其=processtime
//line_wait是该队列一共等了多久？？哦，应该是所有客户的等待时间
//line_wait是客户等待总时间
served++;//服务人数+1
}
if(wait_time2<=0&&!line2.isEmpty())//队列1中有用户处理完了业务
{
line2.deQueue(temp);
wait_time2=temp.ptime();//wait_time是该客户处理业务所用时间
line_wait+=cycle-temp.when();//cycle-temp.when();是该客户一共在队列中等了多久
served++;//服务人数+1
}

if(wait_time>0)//队列1正在处理业务的处理时间-1，因为过了一分钟
wait_time--;
if(wait_time2>0)//队列2正在处理业务的处理时间-1，因为过了一分钟
wait_time2--;
//wait_time=temp.ptime()这里随机设置了wait-time
sum_line+=line.queuecount()+line2.queuecount();//sum_line又是神马东东？？
//sum_line是队伍总长度，每分钟计算一次队伍长度
}

if(customers>0)
{
cout<<"customers accepted:"<<customers<<endl;
cout<<" customers served:"<<served<<endl;
cout<<" turnaways:"<<turnaways<<endl;
cout<<"average queue size:";
cout.precision(2);
cout.setf(ios_base::fixed,ios_base::floatfield);
cout<<(double)sum_line/cyclelimit<<endl;
cout<<"average wait time:"<<(double)line_wait/served<<" minutes"<<endl;
}//我机器上面是18人最接近1分钟，队列长度10,时间100
else
cout<<"No coustomer!"<<endl;
cout<<"Done!"<<endl;
system("pause");
}