pcb.txt

处理机调度算法的实现c++语言编写 利用优先权算法实现

#include "stdio.h"

#include "stdlib.h"

#include "string.h"

typedef struct node /*创建PCB*/     

{     char name[10];    /*进程标识*/

     int prio;     /*进程优先数*/

    int cputime; /*进程占用CPU时间*/
                                        
     int needtime; /*进程完成所需时间*/

     int count;    /*计数器*/

     char state; /*进程的状态*/

     struct node *next; /*链指针*/


}PCB;

PCB *finish,*ready,*tail,*run;

int N;


firstin()            /*创建就绪队列对头指针*/

{

     run=ready;  

     run->state='R';  

     ready=ready->next; 

}



void prt(char algo)    /*演示进程调度*/

{

     PCB *p;

     printf("     NAME    CPUTIME     NEEDTIME     PRIORITY     STATUS\n");

     if(run!=NULL)

     printf("    %-10s%-10d%-10d%-10d %c\n",run->name,

         run->cputime,run->needtime,run->prio,run->state); 

     p=ready; 

     while(p!=NULL)

     {    printf("    %-10s%-10d%-10d%-10d %c\n",p->name,

        p->cputime,p->needtime,p->prio,p->state);

        p=p->next;

     }

     p=finish; 

     while(p!=NULL)

     {    printf("    %-10s%-10d%-10d%-10d %c\n",p->name,

        p->cputime,p->needtime,p->prio,p->state);

        p=p->next;

     }

     getch(); 

}


insert(PCB *q)

{

     PCB *p1,*s,*r;

     int b;

     s=q;

     p1=ready;

     r=p1;

     b=1;

     while((p1!=NULL)&&b)

        if(p1->prio>=s->prio)

        {

       r=p1;

       p1=p1->next;

        }

        else

       b=0;

     if(r!=p1)

     {

        r->next=s;

        s->next=p1;