7.c

#include<stdio.h>
#include<stdlib.h>
struct proc
{
	int id;
	int arrival;
	int burst;
	int rem;
	int wait;
	int finish;
	int turnaround;
	float ratio;
}process[10];
struct proc temp;
	int no;
	int chkprocess(int);
	int nextprocess();
	void roundrobin(int, int, int[], int[]);
	void srtf(int);
	main()
	{
		int n,tq,choice;
		int bt[10],st[10],i,j,k;
		for(; ;)
		{
			printf("Enter the choice \n");
			printf(" 1. Round Robin\n 2. SRT\n 3. Exit \n");
			scanf("%d",&choice);
			switch(choice)
			{
				case 1:
				printf("Round Robin scheduling algorithm\n");
				printf("Enter number of processes:\n");
				scanf("%d",&n);
				printf("Enter burst time for sequences:");
				for(i=0;i<n;i++)
				{
					scanf("%d",&bt[i]);
					st[i]=bt[i];
				}
				printf("Enter time quantum:");
				scanf("%d",&tq);
				roundrobin(n,tq,st,bt);
				break;
				case 2:
				printf("\n \n ---SHORTEST REMAINING TIME NEXT---\n \n ");
				printf("\n \n Enter the number of processes: ");
				scanf("%d", &n);
				srtf(n);
				break;
				case 3: exit(0);
			}
		}
	}
	void roundrobin(int n,int tq,int st[],int bt[])
	{
		int time=0;
		int tat[10],wt[10],i,count=0,swt=0,stat=0,temp1,sq=0,j,k;
		float awt=0.0,atat=0.0;
		while(1)
		{
			for(i=0,count=0;i<n;i++)
			{
				temp1=tq;
				if(st[i]==0)
				{
					count++;

					continue;
				}
				if(st[i]>tq)
				st[i]=st[i]-tq;
				else
				if(st[i]>=0)
				{
					temp1=st[i];
					st[i]=0;
				}
				sq=sq+temp1;
				tat[i]=sq;
			}
			if(n==count)

			break;
		}
		for(i=0;i<n;i++)

		{
			wt[i]=tat[i]-bt[i];

			swt=swt+wt[i];
			stat=stat+tat[i];
		}
		awt=(float)swt/n;
		atat=(float)stat/n;
		printf("Process_no Burst time Wait time Turn around time\n");
		for(i=0;i<n;i++)
		printf("%d\t\t%d\t\t%d\t\t%d\n",i+1,bt[i],wt[i],tat[i]);
		printf("Avg wait time is %f\n Avg turn around time is %f\n",awt,atat);
	}
	int chkprocess(int s)
	{
		int i;
		for(i = 1; i <= s; i++)
		{
			if(process[i].rem != 0)
			return 1;
		}
		return 0;
	}

	int nextprocess()
	{
		int min, l, i;
		min = 32000;
		for(i = 1; i <= no; i++)
		{
			if( process[i].rem!=0 && process[i].rem < min)
			{
				min = process[i].rem;
				l = i;
			}
		}
		return l;
	}
void srtf(int n)
{
int i,j,k,time=0;
float tavg,wavg;
for(i = 1; i <= n; i++)
{
process[i].id = i;
printf("\n\nEnter the arrival time for process %d: ", i);
scanf("%d", &(process[i].arrival));
printf("Enter the burst time for process %d: ", i);
scanf("%d", &(process[i].burst));
process[i].rem = process[i].burst;
}
for(i = 1; i <= n; i++)
{
for(j = i + 1; j <= n; j++)
{
if(process[i].arrival > process[j].arrival)
{
temp = process[i];
process[i] = process[j];
process[j] = temp;
}
}
}
no = 0;
j = 1;
while(chkprocess(n) == 1)
{
if(process[no+1].arrival>time)
{
time++;
continue;
}
if(process[no + 1].arrival == time)
{
while(process[no+1].arrival==time)
no++;
if(process[j].rem==0)
process[j].finish=time;
j = nextprocess();
}
if(process[j].rem != 0)
{
process[j].rem--;
for(i = 1; i <= no; i++)
{
if(i != j && process[i].rem != 0)
process[i].wait++;
}
}
else
{
process[j].finish = time;
j=nextprocess();
time--;
k=j;
}
time++;
}
process[k].finish = time;
printf("\n\n\t\t\t---SHORTEST REMAINING TIME FIRST---");
printf("\n\n Process Arrival Burst Waiting Finishing turnaround Tr/Tb \n");
printf("%5s %9s %7s %10s %8s %9s\n\n", "id", "time", "time", "time",
"time", "time");
for(i = 1; i <= n; i++)
{
process[i].turnaround = process[i].wait + process[i].burst;
process[i].ratio = (float)process[i].turnaround / (float)process[i].burst;
printf("%5d %8d %7d %8d %10d %9d %10.1f ", process[i].id, process[i].arrival,
process[i].burst, process[i].wait, process[i].finish, process[i].turnaround,
process[i].ratio);
tavg=tavg+ process[i].turnaround;
wavg=wavg+process[i].wait;
printf("\n\n");
}
tavg=tavg/n;
wavg=wavg/n;
printf("tavg=%f\t wavg=%f\n",tavg,wavg);
}