operatingSystemMLFQ/osPROJECT at master · sumit1717/operatingSystemMLFQ · GitHub

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#include<iostream>
#include<queue>
#define arr 100

using namespace std;
void robin();
queue<int> que;
int tquan= 4,time;
int f[arr],rtf[arr],qt[arr];//to chk wether p ic complete or not
int arival[arr],burst[arr],prior[arr],respT[arr],full[arr],fe[arr],pid[arr];
int sc=0,slc=-1,lc=0;//counters

main()
{
    int i=0,n=0,min,sum=0;
    cout<<"Enter number of processes: \n";
    cin>>n;
    cout<<"ProcessId ArrivalTime BurstTime Prirority \n";
    for(i=0;i<n;i++)
    { cin>>pid[i]>>arival[i]>>burst[i]>>prior[i];
      if(arival[i]>lc)
    	lc=arival[i];
        sum+=burst[i];
    	respT[i]=burst[i];
    } cout<<endl;
    min=arr;
    for(time=0;!que.empty()||time<=sum+lc;time++){
      min=arr;
      sc=-1;
      for(i=0;i<n;i++)
      {
	if(arival[i]<=time && prior[i]<min&&respT[i]>0&&!f[i])
      	{
           min=prior[i];
           sc=i;
        	}}
	if(sc==-1 && !que.empty())
      {
      	  if(slc !=-1 && respT[slc]==0)
      {
	     full[slc]=time;
             f[slc]=1;
        	}
        slc=-1;
        robin();
        continue;
      }
      else if(sc!=-1 && !que.empty() && slc==-1)
      {
      	if(qt[que.front()]<=4 && qt[que.front()]>0)
      	{
      	que.push(que.front());
      	que.pop();
        } }
      if(sc!=-1 && !rtf[sc])
      {
      	fe[sc]=time-arival[sc];
      	rtf[sc]=1;
      }
      if( sc!=slc && slc!=-1 && !f[slc])
      {
      	que.push(slc);
      	f[slc]=1;
      }
      if(sc !=-1)
      	respT[sc]--;
      if((sc !=-1) && ((respT[sc]==0) ||(burst[sc]-respT[sc])==tquan))
      {
      	if((burst[sc]-respT[sc])==tquan && respT[sc]!=0)
      	{
      	   f[sc]=1;
      	   que.push(sc);
        	}
       	else if(sc!=-1)
       	{
	      full[sc]=time+1;
              f[sc]=1;
        	}}
      slc=sc;
    }
    cout<<"ProcessId  ResponseT   FullT   WaitingT \n";
   for(int i=0;i<n;i++)
       cout<<"    "<<pid[i]<<"\t\t"<<fe[i]<<"\t"<<full[i]<<"  \t"<<full[i]-burst[i]-arival[i]<<endl;
    return 0;
   }
void robin()
{
if(!que.empty())
{
  if(respT[que.front()]>0 && qt[que.front()]<4)
  {
    qt[que.front()]++;
    respT[que.front()]--;
      if(respT[que.front()]==0)
	  {
        full[que.front()]=time+1;
        que.pop();
        }
      if(respT[que.front()]!=0 && qt[que.front()]==4)
	  {
	    qt[que.front()]=0;
            que.push(que.front());
            que.pop();
        }
     }
  }
}