1 #include <stdio.h>  2 #include <stdlib.h>  3 typedef struct  node//一个进程的结构  4 {  5     int pid;   //进程ID号  6     int priority;  //进程优先数  7     int time;     //进程分配的时间片  8     char state;   //进程的状态  9     struct node * next; 10 }pcb; 11  12  13 pcb * p; 14 pcb * creat();  //进程的创建 15 int output();   //输出队列信息 16 pcb * insert(pcb * head,pcb * p); //进程p的插入 17 pcb * del(pcb * head,pcb * p); 18 int priority(pcb * head); 19 int s=0; 20 int a[10000]; 21  22  23 pcb * creat()   //基于进程链表的创建 24 { 25     pcb * p1,* head; 26     int i,num; 27     head=NULL; 28     printf("进程个数:\n"); 29     scanf("%d",&num); 30     for(i=0;i<num;i++) 31     { 32         printf("请输入第%d个进程的信息:\n",i+1); 33         p1=(pcb *)malloc(sizeof(pcb)); 34         printf("输入进程优先数:\n"); 35         scanf("%d",&p1->priority); 36         printf("输入进程分配的时间:\n"); 37         scanf("%d",&p1->time); 38         p1->pid=i+1; 39         printf("\n"); 40         p1->state=‘W‘; 41         head=insert(head,p1); 42     } 43     return head; 44 } 45  46 int output(pcb * head)     //输出链表信息 47 { 48     pcb * p; 49     p=head; 50     do 51     { 52         printf("%d  %d  %d  %c\n",p->pid,p->priority,p->time,p->state); 53         p=p->next; 54     } 55     while(NULL!=p); 56     return 0; 57 } 58  59 pcb * insert(pcb * head,pcb * p)  //将p按照优先级插入链表 60 { 61     pcb * p0,* p1,* p2; 62     p1=head; 63     p0=p; 64     if(head==NULL) 65     { 66         head=p0; 67         p0->next=NULL; 68     } 69     else 70     { 71         while((p1->priority>=p0->priority) && (p1->next!=NULL))   //寻找位置 72         { 73             p2=p1; 74             p1=p1->next; 75         } 76         if(p0->priority>p1->priority)  //如果p0大于p1的优先级,找到存放的位置 77         { 78             if(head==p1)   //并且p1正在运行,此时链表为p1,NULL 79             { 80                 head=p0; 81             } 82             else 83             { 84                 p2->next=p0; 85                 p0->next=p1; 86             } 87         } 88         else              //因为p1->next=NULL跳出 89         { 90             p1->next=p0; 91             p0->next=NULL; 92         } 93     } 94     return head; 95 } 96  97 pcb * del(pcb * head,pcb * p) //进程p的删除 98 { 99     p->state=‘F‘;100     printf("进程%d已经DELETE\n",p->pid);101     printf("\n");102     return head;103 }104 105 int priority(pcb * head)  //进程的调度106 {107     char flag;108     pcb * p,* rp;109     p=head;110     while(NULL!=p)111     {112         rp=p;113         p=p->next;114         do115         {116             flag=‘y‘;117             printf("进程%drunning\n",rp->pid);118             rp->state=‘R‘;119             rp->priority=rp->priority-3;120             rp->time--;121             a[s++]=rp->pid;122             output(rp);123             rp->state=‘W‘;124             printf("\n");125             if(0==rp->time)126                 p=del(p,rp);127             else128             {129                  if((p==NULL) || (rp->priority>=p->priority))130                      flag=‘n‘;131                  else132                  {133                      p=insert(p,rp);134                      printf("当前链表信息\n");135                      output(p);136                      printf("\n");137                  }138             }139         }140         while(flag==‘n‘);141     }142     return 0;143 }144 145 int main()146 {147     int i;148     pcb * head=NULL;149     printf("please input data!\n");150     head=creat();151     printf("链表信息\n");152     output(head);153     printf("\n");154     printf("begin running!\n");155     printf("\n");156     priority(head);157     for(i=0;i<s;i++)158     {159         printf("%d",a[i]);160         if(i!=s-1)161             printf("-->");162     }163     printf("\n");164     return 0;165 }