短作业优先算法试验报告

实验短作业优先SJF进程调度算法模拟一、实验目的模拟单处理器系统的进程调度，采用短作业优先的进程调度算法作为进程设计算法，以加深对进程的概念及进程调度算法的理解．二、实验内容如进程信息如下：structPCBpcb[N]= {{"AAA",0,4},{"BBB",1,3},{"CCC",2,5},{"DDD",15,2},{"EEE",4,4}};进程名到达时间运行时间完成时间周转时间A0444B1376C251614D152183E44117#include<stdio.h>#include<string.h>#include<stdlib.h>#include<conio.h>#defineN5structPCB{ charname[8]; intarrive_time; intrun_time; intfinish_time; intzhouzhuan_time; floatdaiquan_time;};floatpinjun_zhouzhuan_time;floatpinjun_daiquan_time;structPCBpcb[N]={{"DDD",3,2},{"AAA",0,4},{"BBB",1,3},{"CCC",2,5},{"EEE",4,4}};voidoutput(){printf("进程名到达时间运行时间完成时间周转时间带权周转时间\n"); for(inti=0;i<N;i++) { printf("%s%d%d%d%d%f\n",pcb[i].name,pcb[i].arrive_time,pcb[i].run_time,pcb[i].finish_time,pcb[i].zhouzhuan_time,pcb[i].daiquan_time); }}voidsortPCB(){ structPCBtemp;inti,j; for(i=0;i<N-1;i++) for(j=i+1;j<N;j++) if(pcb[i].arrive_time>pcb[j].arrive_time) { temp=pcb[j]; pcb[j]=pcb[i]; pcb[i]=temp; }}voidmain(){ inti; printf("进程初始状态\n"); output(); printf("进程按到达时间排序后的状态\n"); sortPCB(); output(); for(i=0;i<N;i++) { //下面计算本进程的完成时间 if(i==0) pcb[i].finish_time=pcb[i].run_time+pcb[i].arrive_time; else if(pcb[i].arrive_time<pcb[i-1].finish_time) pcb[i].finish_time=pcb[i-1].finish_time+pcb[i].run_time; else pcb[i].finish_time=pcb[i].arrive_time+pcb[i].run_time; //下面计算本进程的周转时间 pcb[i].zhouzhuan_time=pcb[i].finish_time-pcb[i].arrive_time; //下面计算本进程的带权周转时间pcb[i].daiquan_time=(float)pcb[i].zhouzhuan_time/pcb[i].run_time; } inttotal_zhouzhuan_time=0; floattotal_daiquan_time=0; for(i=0;i<N;i++) { total_zhouzhuan_time+=pcb[i].zhouzhuan_time; total_daiquan_time+=pcb[i].daiquan_time; } pinjun_zhouzhuan_time=(float)total_zhouzhuan_time/N; pinjun_daiquan_time=total_daiquan_time/N; printf("计算后的结果输出\n");