//This program simulates the Round-Robin scheduling algorithm.
//All processes are assumed to have arrived at the same time.
//Author's Name:	Low Chee Tat 1001150277
//Subject Code:		TOS 2111 Operating Systems
//Program Title:	Round-Robin Scheduling Simulation Program implemented by C++

#include <iostream.h>
#include <stdlib.h>
#include <conio.h>


class Process
{
	private:	
		int totalbittime;

	public:

		int ReturnValue()
		{
			return totalbittime;
		}
		
		void getTime()
		{
			cout<<"Please enter burst time of this process: ";
			cin>>totalbittime;
		}


		void display(int timeQ)
		{
			
				totalbittime-=timeQ;
				cout<<totalbittime;
					
		}

};

void main()
{	
	system("cls");
	//clrscr();
	Process *p;
	int num;
	int qtime;
	int temp;
	int k=0;
	int s;
	char quit;
	
	cout<<"This program simulates the Round-Robin scheduling process "<<endl;
	
	cout<<"How many process do you want to view?";
	cin>>num;
	

	p=new Process[num];
	
	for(int i=0;i<num;i++)
	{
		p[i].getTime();
	}

	cout<<"Enter time quantum: ";
	cin>>qtime;

	temp=qtime;

	cout<<"Press 'q' to quit:"<<endl;
	cout<<"Running Time     ";
	cout<<"Process     ";
	cout<<"Remaining Burst Time"<<endl;
	for(int j=0;j<55;j++)
		cout<<"_";

	cout<<endl;

	do{
		s=k%num;
		if(temp<10)
			cout<<"     "<<temp<<"             ";
		else
			cout<<"    "<<temp<<"             ";

		cout<<"p"<<s<<"           ";

		
		if(p[s].ReturnValue()<=0)
		{
			cout<<"   "<<"0";
			quit=getch();	
			
		}
		else
		{
			if(temp<10)
			{
				cout<<"     ";
				p[s].display(qtime);
			}
			else
			{
				cout<<"     ";
				p[s].display(qtime);
			}		
		}
		
		temp+=qtime;

		cout<<endl;
		k++;
		
		if(quit=='q')
			exit(1);
	
	}while(num>0);

	//getch();
	system("pause");
}