practical no 3

// C++ program for implementation of RR scheduling
#include<iostream>
using namespace std;

void findWaitingTime(int processes[], int n,
int bt[], int wt[], int quantum)
{
int rem_bt[n];
for (int i = 0 ; i < n ; i++)
rem_bt[i] = bt[i];
int t = 0; // Current time
while (1)
{
bool done = true;
for (int i = 0 ; i < n; i++)
{
if (rem_bt[i] > 0)
{
done = false; // There is a pending process
if (rem_bt[i] > quantum)
{
t += quantum;
rem_bt[i] -= quantum;
}
else
{

				t = t + rem_bt[i]; 

				
				wt[i] = t - bt[i]; 

			
				rem_bt[i] = 0; 
			} 
		} 
	} 
	if (done == true) 
	break; 
} 

}
void findTurnAroundTime(int processes[], int n,
int bt[], int wt[], int tat[])
{
for (int i = 0; i < n ; i++)
tat[i] = bt[i] + wt[i];
}
void findavgTime(int processes[], int n, int bt[],
int quantum)
{
int wt[n], tat[n], total_wt = 0, total_tat = 0;
findWaitingTime(processes, n, bt, wt, quantum);
findTurnAroundTime(processes, n, bt, wt, tat);
cout << "PN\t "<< " \tBT "
<< " WT " << " \tTAT\n";
for (int i=0; i<n; i++)
{
total_wt = total_wt + wt[i];
total_tat = total_tat + tat[i];
cout << " " << i+1 << "\t\t" << bt[i] <<"\t "
<< wt[i] <<"\t\t " << tat[i] <<endl;
}
cout << "Average waiting time = "
<< (float)total_wt / (float)n;
cout << "\nAverage turn around time = "
<< (float)total_tat / (float)n;
}
int main()
{
int processes[] = { 1, 2, 3};
int n = sizeof processes / sizeof processes[0];
int burst_time[] = {10, 5, 8};
int quantum = 2;
findavgTime(processes, n, burst_time, quantum);
return 0;
}