CPU-scheduling/sjf.c at master · something123something/CPU-scheduling · GitHub

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#include<stdio.h>
#include<string.h>
struct process{
char name[10];
int at,bt,wt,tt,sta;
}p[20];
struct done{
char name[10];
int st,ct;
}d[20];
void read(int n)
{
int i;
printf("\nEnter the details of the processes\n");
for(i=0;i<n;i++)
{
 printf("\nEnter the name:");
 scanf("%s",p[i].name);
 printf("\nEnter the at:");
 scanf("%d",&p[i].at);
 printf("\nEnter the bt:");
 scanf("%d",&p[i].bt);
 p[i].sta=0;
}
}
int sjf(int n)
{
	int ls,i,j,k,num,idle,found;
	idle=0;
	for(ls=0,i=0,num=0;ls<n;)
	{
		found=0;
		for(j=0;j<n;j++)
		{
		if(found==0 && p[j].sta==0 && p[j].at<=i)
			{
				found++;
				k=j;
			}
		if(found>0 && p[j].sta==0 && p[j].at<=i)
			{
				if(p[j].bt<p[k].bt)
					{
					k=j;
					}
			}
		}
		if(found==0 && idle==0)
		{
			idle=1;
			strcpy(d[num].name,"idle");
			d[num].st=i;
			i++;
		}
		else if(found==0 && idle==1)
		{
			i++;
		}
		else if(found>0)
		{
			if(idle==1)
				{
				d[num].ct=i;
				num++;
				idle=0;
				}
			strcpy(d[num].name,p[k].name);
			d[num].st=i;
			d[num].ct=i+p[k].bt;
			num++;
			p[k].wt=i-p[k].at;
			p[k].tt=p[k].wt+p[k].bt;
			i=i+p[k].bt;
			p[k].sta=1;
			ls++;
		}
	}
return(num);
}
void display(int n,int num)
{
  float awt,att;
  awt=att=0;
  int i,j;float g,h;
	g=h=0;
  for(i=0;i<n;i++)
  {
	g+=p[i].wt;
	h+=p[i].tt;
  }
	awt=g/n;
	att=h/n;
	printf("average wt =%f and tt =%f",awt,att);

  printf("\nname\tat\tbt\twt\ttt\n");
  for(j=0;j<n;j++)
  {
  printf("%s\t%d\t%d\t%d\t%d\n",p[j].name,p[j].at,p[j].bt,p[j].wt,p[j].tt);
  }
  printf("\n\nGantt Chart\n_______________________\n");
	for(i=0;i<num;i++)
	{
		printf("--------");
	}
	printf("\n");
	for(i=0;i<num;i++)
	{
		printf("|%s\t",d[i].name);
	}
	printf("|\n");
	for(i=0;i<num;i++)
	{
		printf("--------");
	}
	printf("\n");
	for(i=0;i<num;i++)
	{
		printf("%d\t",d[i].st);
	}
	printf("%d\n",d[i-1].ct);
  printf("\n");


}
void main()
{
int n,i,j,k,p;
printf("\nEnter the number of process:");
scanf("%d",&n);
read(n);
p=sjf(n);
display(n,p);
}