如何 用C语言 实现作业调度算法(FCFS,SJF)

[dd490166171]

如何 用C语言 实现作业调度算法(FCFS,SJF)
有那位高手能指点指点吗?

[yashiro_]

#include <stdio.h>

#define getjcb(type) (type*)malloc(sizeof(type))
//#define NULL 0

int n=0, time = 0;
float eti, ewi;

struct jcb
{ 
	char name[10];           /* 作业名 */
	char state;              /* 作业状态 */
	int ts;                  /* 提交时间 */
	float super;               /* 优先权 */
	int tb;                  /* 开始运行时间 */
	int tc;                  /* 完成时间 */
	float ti;                /* 周转时间 */
	float wi;                /* 带权周转时间 */
	int ntime;               /* 作业所需运行时间 */
	char resource[10];       /* 所需资源 */
	struct jcb *link;        /* 结构体指针 */
} *p,*q,*head=NULL;

typedef struct jcb JCB;

void inital()
{
	int i;

	printf("\nInput jcb num\n");
	scanf("%d", &n);
	
	printf("Input\nname\tts\tntime\tresource\n");
	for(i = 0; i < n; i++)
	{
		p = getjcb(JCB);
		scanf("%s\t%d\t%d\t%s", &p->name, &p->ts, &p->ntime, &p->resource);
		p->state = 'W';
		p->link = NULL;

		if(head == NULL)
			head = q = p;
		else
		{
			q->link = p;
			q = p;
		}
}
}

void fileinput()
{
	FILE *fp;
	int i;
	if((fp = fopen("os2.txt","r")) == NULL)
		printf(" open error! \n");

	fscanf(fp, "%d\n", &n);

	for(i = 0; i < n; i++)
	{
		p = getjcb(JCB);
		fscanf(fp,"%s%d%d%s", &p->name, &p->ts, &p->ntime, &p->resource);

		p->state = 'W';
		p->link = NULL;
		if(head == NULL)
			head = q = p;
		else
		{
			q->link = p;
			q = p;
		}
	}
	fclose( fp );
}



void print(JCB *pr, int m)
{
	JCB *p;
	printf("\ntime=%d", time);
	if(m == 3)
	{
		printf("\nname\tstate\tts\tntime\tsuper\tsource\ttb\ttc\tti\twi\n");
		printf("%s\t%c\t%d\t%d\t%4.2f\t%s\t%d\t%d\t%4.2f\t%4.2f\n",
		pr->name, pr->state, pr->ts, pr->ntime, pr->super, pr->resource, pr->tb, pr->tc, pr->ti, pr->wi);
	}
	else
	{
		printf("\nname\tstate\tts\tntime\tsource\ttb\ttc\tti\twi\n");
		printf("%s\t%c\t%d\t%d\t%s\t%d\t%d\t%4.2f\t%4.2f\n",
		pr->name, pr->state, pr->ts, pr->ntime, pr->resource, pr->tb, pr->tc, pr->ti, pr->wi);
	}
	p = head;
	do{
		if(p->state == 'W')
			if(m==3)
			{
				printf("%s\t%c\t%d\t%d\t%4.2f\t%s\n",
				p->name, p->state, p->ts, p->ntime, p->super, p->resource);
			}
			else
			{
				printf("%s\t%c\t%d\t%d\t%s\n",
				p->name, p->state, p->ts, p->ntime, p->resource);
			}
		p = p->link;
	}while( p != NULL );

	p = head;
	do{
		if(p->state == 'F')
			if(m == 3){
				printf("%s\t%c\t%d\t%d\t%4.2f\t%s\t%d\t%d\t%4.2f\t%4.2f\n",
				p->name, p->state, p->ts, p->ntime, p->super, p->resource, p->tb, p->tc, p->ti, p->wi);
			}
			else{
				printf("%s\t%c\t%d\t%d\t%s\t%d\t%d\t%4.2f\t%4.2f\n",
				p->name, p->state, p->ts, p->ntime, p->resource, p->tb, p->tc, p->ti, p->wi);
			}
			p = p->link;
	}while( p != NULL );
}

void last()
{
    eti /= n;
	ewi /= n;
    printf("\neti=%7.3f\tewi=%7.3f\n", eti, ewi);
}

void super()
{
	JCB *padv;
	padv = head;

	do{
		if(padv->state == 'W' && padv->ts <= time)
			padv->super = (float) (time-padv->ts+padv->ntime)/padv->ntime;

		padv = padv->link;
	}while( padv != NULL );
}

running(JCB *p, int m)
{
    p->tb = time;
	p->state = 'R';
    p->tc = p->tb + p->ntime;
    p->ti = (float) (p->tc-p->ts);
    p->wi = (float) (p->ti/p->ntime);
    eti += p->ti;
    ewi += p->wi;

    print(p, m);

    time += p->ntime;
    p->state = 'F';
    printf("\n%s has been finished!\npress any key to continue...\n", p->name);
    getchar();
}

void hrn(m)
{
	JCB *min;
	int i, iden;

	for(i = 0; i < n; i++)
	{
		p = min = head;
		iden = 1;
		super();

		do{
			if(p->state == 'W' && p->ts <= time)
				if(iden)
				{
					min=p;
					iden=0;	
				}
				else if(p->super > min->super)
					min=p;

			p=p->link;
		}while( p != NULL );

		if( iden )
		{
			i--;
			time++;
			printf("\ntime=%d:\tno JCB submib...wait...", time);
			if(time>1000)
			{
				printf("\nruntime is too long...error...");
				getchar();
			}
		}
		else
		{
			running(min, m);
		}
	}
}

void sjf(int m)
{
    JCB *min;
    int i, iden;

    for(i = 0; i < n; i++)
	{
        p = min = head;
		iden = 1;
		
        do{
            if(p->state == 'W' && p->ts <= time)
                if( iden )
				{
					min = p;
					iden = 0;
				}
                else if(p->ntime < min->ntime)
					min=p;

            p = p->link;
        }while( p != NULL );

        if( iden )
		{
            i--;
			printf("\ntime=%d:\tno JCB submib...wait...", time);
			time++;
            if(time > 100)
			{
				printf("\nruntime is too long...error");
				getchar();
			}
		}
        else
		{
            running(min, m);
        }
    }
}

void fcfs(int m)
{
    int i,iden;
    printf("\n\nthe jcb is runing...");

    for(i = 0; i < n; i++)
	{
        p = head;
		iden = 1;
        do{
            if(p->state == 'W' && p->ts <= time)
				iden = 0;

            if( iden )
				p = p->link;
        }while(p != NULL && iden);

        if( iden )
		{
            i--;
			printf("\ntime=%d:\tno JCB submib...wait...", time);
			time++;
            if(time > 100)
			{
				printf("\nruntime is too long...error");
				getchar();
			}
		}
        else
		{
            running(p, m);
        }
    }
}



void runjcb(int m)
{
    printf("\n\nstart running jcb...");
    switch( m )
	{
        case 1:
			fcfs( m );
			break;
        case 2:
			sjf( m );
			break;
        case 3:
			hrn( m );
			break;
        default:
			printf("\nrunjcb error...\n");
			return ;
    }
}

void fileway()
{
    printf("\nadopts the file way to input the datas...y/n:");
    if(getchar() == 'y')
		fileinput();
    else
		inital();
}

void start()
{
    int m;
    char str[100] = "\n select algorithm \n 1.FCFS \n 2.SJF \n 3.HRN \n" ;
    printf("%s", str);
	
    m=getchar()-48;

    fileway();

    if(1 <= m && m <= 3)
		runjcb( m );
    else
	{
        printf("\nselect error!try again...\n");
        start();
    }
    last();
}


void main()
{
	start();
    printf("\nfinished!");
    getchar();
}

[yashiro_]

输入时有点问题，

将getchar替换成getch就好用了。

[lxhdj2008]

二楼老大强

[dd490166171]

多谢了!

[dd490166171]

不知道有没有不用指针的方法呢?

[susemm]

[Quote=引用 5 楼 dd490166171 的回复:]
不知道有没有不用指针的方法呢?
[/Quote]
用c语言不用指针？？？？
please kill me~~~~~~~~~~~~~

[JackeyChung]

二楼强！

[muyueshu]

真给力！！！