磁盘位示图管理

 

//设计一个按优先数调度算法实现处理器调度的程序。
#include <iostream.h>
typedef struct p
{
    char name[];
    int time;
    int num;
    struct p *next;
}plist;
void creat();
void sort1(plist *L); 
void sort2(plist *L);
void display(plist *L); 
void done(plist *L); 
plist *L;
int main()
{
    creat();
    display(L); 
    done(L); 
    getchar();
    getchar(); 
}    
void creat()
{
    plist *s,*r; 
    L=new plist;
    L->next=NULL;
    r=L; 
    cout<<"              优先数进程调度模拟"<<endl<<endl; 
    cout<<"输入进程的名字,要求运行时间和优先数："<<endl; 
    for(int i=1;i<=5;i++)
    {
        s=new plist; 
        while(1)
        { 
           cout<<"第"<<i<<"个进程：";
           cin>>s->name>>s->time>>s->num;
           if(s->time>0) 
             break;
           else cout<<"输入错误，请重新输入."<<endl;  
        } 
        r->next=s;
        r=s;         
    }
    r->next=NULL; 
    sort1(L);  
}     
void done(plist *L)
{
    while(1)
    { 
    plist *p=L->next;
    if(p==NULL)
    {
        cout<<"所有进程执行完毕."<<endl;
        return;
    }
    else
    {
        cout<<p->name<<"进程运行一个了单位时间."<<endl; 
        p->num-=1;
        p->time-=1; 
        if(p->time==0)
        {
            L->next=p->next; 
            delete p;
            display(L);
        }
        else  
        {
            sort2(L);
            display(L);
        } 
    }   
    } 
}   
void display(plist *L)
{
    plist *p=L->next;
    while(p!=NULL)
    {
        cout<<p->name<<"    "<<p->time<<"    "<<p->num<<endl;
        p=p->next;
    }
    cout<<endl;
} 
void sort1(plist *L)    //链表排序
{  
   plist *p=L->next, *q, *r;
   if(p!=NULL)
   {
      r=p->next;
      p->next=NULL;
      p=r;
      while(p!=NULL)
      {
        r=p->next;
        q=L;
        while(q->next!=NULL&&q->next->num>p->num)
           q=q->next;
        p->next=q->next;
        q->next=p;
        p=r;
      } 
   }      
}        
void sort2(plist *L)
{
    plist *p=L->next,*q,*r;
    L->next=p->next;
    q=L->next;
    r=L;
    while(q!=NULL&&q->num>=p->num)
    {
        r=q;
        q=r->next;
    }    
    r->next=p;
    p->next=q;     
}