FCFS和SJF调度算法1.docx

以下参考的别人的：FCFS和SJF调度算法思想和实现算法算法思想:设计程序模拟进程的先来先服务FCFS和短作业优先SJF调度过程。假设有n个进程分别在T1, ,Tn时刻到达系统，它们需要的服务时间分别为S1, ,Sn。分别采用先来先服务FCFS和短作业优先SJF进程调度算法进行调度，计算每个进程的完成时间，周转时间和带权周转时间，并且统计n个进程的平均周转时间和平均带权周转时间。源程序:#include #include staticconstint N=100;intarrivalTimeN;/到达时间intserviceTimeN;/服务时间intfinishTimeN;/完成时间intWholeTimeN;/周转时间double WeightWholeTimeN;/带权周转时间double averageWT,averageWWT;/平均周转时间intserviceTime_SJFN;int n=0;intnowTime=0;/记录当前时间inti;void FCFS()coutn=FCFS调度算法=n;for(i=0;inowTime)nowTime=arrivalTimei;nowTime+=serviceTimei;finishTimei=nowTime;for(inti=0;in;i+)WholeTimei=finishTimei-arrivalTimei;for(inti=0;in;i+)WeightWholeTimei=(double)WholeTimei/(double)serviceTimei;for(inti=0;in;i+)averageWT+=(double)WholeTimei/n;averageWWT+=(double)WeightWholeTimei/n; void SJF()coutn=SJF调度算法=n;int min=0;nowTime=arrivalTime0+serviceTime0;finishTime0=nowTime;serviceTime_SJF0=100;intallin=0,j,k;for(i=1;in;i+)k=1;min=0;if(allin=0)j=0;while(arrivalTimej=nowTime& jn)allin=1;elsej=n;j=j-1;while(kserviceTime_SJFk)min=k;k+;serviceTime_SJFmin=0;nowTime+=serviceTimemin;finishTimemin=nowTime;for(inti=0;in;i+)WholeTimei=finishTimei-arrivalTimei;for(inti=0;in;i+)WeightWholeTimei=(double)WholeTimei/(double)serviceTimei;averageWT=0;averageWWT=0;for(inti=0;in;i+)averageWT+=(double)WholeTimei/n;averageWWT+=(double)WeightWholeTimei/n;void sortOn()/进程按照到达或者服务时间进行排序int temp;for(inti=0;in;i+)for(int k=0;kn-i-1;k+)if(arrivalTimek+1arrivalTimek)temp=arrivalTimek+1;arrivalTimek+1=arrivalTimek;arrivalTimek=temp;temp=serviceTimek+1;serviceTimek+1=serviceTimek;serviceTimek=temp;void input()coutn;cout100|n=0)cout进程个数必须大于0且小于等于100！请重新输入进程个数endl;cout请输入这N个进程的到达时间：nn; for(inti=0;iM;arrivalTimei=M;coutendl;cout请输入这N个进程的对应的服务时间：nn;for(inti=0;iM;serviceTimei=M;serviceTime_SJFi=M;coutendl;cout您输入的这N个进程的信息如下：nn;sortOn();/进程按照到达时间进行排序cout进程名tt;for(inti=0;in;i+)char c=i+65;coutct;coutn到达时间t;for(inti=0;in;i+)coutarrivalTimeit;coutn服务时间t;for(inti=0;in;i+)coutserviceTimeit;coutendlendl;void output()cout进程名tt;for(inti=0;in;i+)char c=i+65;coutct;cout平均n到达时间t;for(inti=0;in;i+)coutarrivalTimeit;coutn服务时间t;for(inti=0;in;i+)coutserviceTimeit;coutn完成时间t;for(inti=0;in;i+)coutfinishTimeit;coutn周转时间t;for(inti=0;in;i+)coutWholeTimeit;coutaverageWTsetprecis