prog7.c

#include<stdio.h>
#include<stdlib.h>

int arrival[10];
int burst[10];
int rem[10];
int wait[10];
int finish[10];
int turnaround[10];
int flag[10];

void roundrobin(int,int,int[],int[]);
void srtf(int);

int main()
{
  int n,tq,choice;
  int bt[10],st[10],i,j;
  for(;;)
  {
    printf("enter the choice\n1. round robin\n 2.srt 3.Exit\n");
    scanf("%d",&choice);
    switch(choice)
    {
      case 1: printf("enter no. of process:\n");
              scanf("%d",&n);
              printf("enter brust time\n");
              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("enter no. of process:\n");
              scanf("%d",&n);
              srtf(n);
              break;

      case 3:return 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;
  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];
  }

  printf("process_no burst time wait time turnaround 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("average waiting time is %f\n average turnaround time is %f\n",(float)swt/n,(float)stat/n);
}

void srtf(int n)
{
  int stat=0,swt=0,time=0,count=0,i,j,min=999;
  for(i=1;i<=n;i++)
  {
    printf("arrival of p%d:",i);
    scanf("%d",&arrival[i]);
    printf("burst of p%d:",i);
    scanf("%d",&burst[i]);
    rem[i]=burst[i];
    flag[i]=0;
  }

  while(1)
  {
    for(i=1,min=999;i<=n;i++)
      if(arrival[i]<=time&&flag[i]==0)
        if(rem[i]<min)
        {
          min=rem[i];
          j=i;
        }

    time++;
    rem[j]-=1;

    if(rem[j]==0)
    {
      finish[j]=time;
      flag[j]=1;
      count++;
    }

    if(count==n)
      break;
  }

  for(i=1;i<=n;i++)
  {
    turnaround[i]=finish[i]-arrival[i];
    wait[i]=turnaround[i]-burst[i];
    stat+=turnaround[i];
    swt+=wait[i];
  }

  printf("the process table:\n\t process no.\t|finish\t|wait\t|turnaround\t\n");
  for(i=1;i<=n;i++)
    printf("\t%d \t%d \t%d \t%d \t%d \t%d\n",i,arrival[i],burst[i],finish[i],wait[i],turnaround[i]);
  printf("averagewaittime: %f\t avgturnaroundtime: %f\n",(float)swt/n,(float)stat/n);
  return;
}