操作系统页面置换算法RR

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data4.txt输入文件内容：

5
3
A B C D E
0 6 10 16 24
15 10 12 4 8

//
#include <iostream>
#include <queue>
#include <iomanip>
#include <fstream>
using namespace std;typedef struct  
{char name;int ArrivalTime;int ServiceTime;int FinishedTime;int WholeTime;double WeightWholeTime;
}RR;static queue<RR>RRqueue;  //声明一个队列
static double AverageWT =0,AverageWWT=0;
static int q;  //时间片
static int n;  //进程个数
static RR RRarray[100];  //进程结构void Input()
{//文件读取模式ifstream inData;inData.open("./data4.txt");//data.txt表示q = 4的RR调度算法//data2.txt表示q = 1的RR调度算法inData>>n;inData>>q;for (int i=0;i<n;i++){inData>>RRarray[i].name;}for (int i=0;i<n;i++){inData>>RRarray[i].ArrivalTime;}for (int i=0;i<n;i++){inData>>RRarray[i].ServiceTime;}//用户输入模式//cout<<"****************************************************************"<<endl;//cout<<"please input the number of process n = ";//cin>>n;//cout<<"please input the number of timeSlice q = ";//cin>>q;//cout<<"please input the name of process:"<<endl;//for (int i=0;i<n;i++)//{//	cin>>RRarray[i].name;//}//cout<<"please input the ArrivalTime of process:"<<endl;//for (int i=0;i<n;i++)//{//	cin>>RRarray[i].ArrivalTime;//}//cout<<"please input the ServiceTime of process:"<<endl;//for (int i=0;i<n;i++)//{//	cin>>RRarray[i].ServiceTime;//}cout<<"****************************************************************"<<endl;//输出用户所输入的信息cout<<"The information of processes is the following:"<<endl;cout<<setw(10)<<"processName"<<" ";cout<<setw(10)<<"ArrivalTime"<<" ";cout<<setw(10)<<"ServiceTime"<<" "<<endl;for (int i=0;i<n;i++){cout<<setw(10)<<RRarray[i].name<<" ";cout<<setw(10)<<RRarray[i].ArrivalTime<<" ";cout<<setw(10)<<RRarray[i].ServiceTime<<" "<<endl;}cout<<"****************************************************************"<<endl;
}void RRAlgorithm()
{char processMoment[100];   //存储每个时间片p对应的进程名称RRqueue.push(RRarray[0]);int processMomentPoint = 0;int CurrentTime=0;int tempTime;   //声明此变量控制CurrentTime的累加时间，当前进程的服务时间小于时间片q的时候，起到重要作用int i=1;  //指向还未处理的进程的下标int finalProcessNumber = 0;   //执行RR算法后，进程的个数int processTime[50];//CurrentTime的初始化if (RRarray[0].ServiceTime>=q){CurrentTime = q;}else{CurrentTime = RRarray[0].ServiceTime;}while(!RRqueue.empty()){	for (int j=i;j<n;j++)   //使得满足进程的到达时间小于当前时间的进程都进入队列{if (RRarray[j].name!=NULL && CurrentTime >= RRarray[j].ArrivalTime) {RRqueue.push(RRarray[j]);i++;}}if (RRqueue.front().ServiceTime<q){tempTime = RRqueue.front().ServiceTime;}else{tempTime = q;}RRqueue.front().ServiceTime -= q;   //进程每执行一次，就将其服务时间 -q//将队首进程的名称放入数组中processMoment[processMomentPoint] = RRqueue.front().name;processMomentPoint++;processTime[finalProcessNumber] = tempTime;finalProcessNumber++;if (RRqueue.front().ServiceTime <= 0)  //把执行完的进程退出队列{//RRqueue.front().FinishedTime = CurrentTime;RRqueue.pop();   //如果进程的服务时间小于等于，即该进程已经服务完了，将其退栈}else{//将队首移到队尾RRqueue.push(RRqueue.front());RRqueue.pop();}CurrentTime += tempTime;	}//进程输出处理   每个时间段对应的执行的进程cout<<"各进程的执行时刻信息："<<endl;cout<<"  "<<"0时刻 --> "<<setw(2)<<processTime[0]<<"时刻";processTime[finalProcessNumber]=0;int time = processTime[0];int count = 0;for (int i=0;i<finalProcessNumber;i++){		count = 0;cout<<setw(3)<<processMoment[i]<<setw(3)<<endl;while(RRarray[count].name!=processMoment[i] && count<n){count++;}RRarray[count].FinishedTime = time;if (i<finalProcessNumber - 1){cout<<setw(3)<<time<<"时刻"<<" --> "<<setw(2)<<time + processTime[i+1]<<"时刻"<<setw(3);time += processTime[i+1];		}}cout<<endl;//周转时间、带权周转时间、平均周转时间、带权平均周转时间的计算//1. 周转时间 = 完成时间 - 到达时间//2. 带权周转时间 = 周转时间/服务时间for (int i=0;i<n;i++){RRarray[i].WholeTime = RRarray[i].FinishedTime - RRarray[i].ArrivalTime;RRarray[i].WeightWholeTime = (double)RRarray[i].WholeTime/RRarray[i].ServiceTime;}double x=0,y=0;for (int i=0;i<n;i++){x += RRarray[i].WholeTime;y += RRarray[i].WeightWholeTime;}AverageWT = x/n;AverageWWT = y/n;}void display()
{cout<<"******************************************************"<<endl;cout<<"RR调度算法执行后：进程相关信息如下："<<endl;cout<<setw(10)<<"进程名（ID）"<<" ";cout<<setw(10)<<"到达时间"<<" ";cout<<setw(10)<<"服务时间"<<" ";cout<<setw(10)<<"完成时间"<<" ";cout<<setw(10)<<"周转时间"<<" ";cout<<setw(10)<<"带权周转时间"<<endl;for (int i = 0;i<n;i++){cout<<setw(10)<<RRarray[i].name<<" ";cout<<setw(10)<<RRarray[i].ArrivalTime<<" ";cout<<setw(10)<<RRarray[i].ServiceTime<<" ";cout<<setw(10)<<RRarray[i].FinishedTime<<" ";cout<<setw(10)<<RRarray[i].WholeTime<<" ";cout<<setw(10)<<RRarray[i].WeightWholeTime<<" "<<endl;;}cout<<"所有进程的平均周转时间 = "<<AverageWT<<endl;cout<<"所有进程的平均带权周转时间 = "<<AverageWWT<<endl;cout<<"******************************************************"<<endl;
}int main()
{Input();RRAlgorithm();display();system("pause");return 0;
}

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