#include
// Function to find the waiting time for all
// processes
void findWaitingTime(int processes[], int n,
int bt[], int wt[], int quantum)
{
// Make a copy of burst times bt[] to store remaining
// burst times.
int rem_bt[n];
for (int i = 0 ; i < n ; i++)
rem_bt[i] = bt[i];
int t = 0; // Current time
// Keep traversing processes in round robin manner
// until all of them are not done.
while (1)
{
int done = 1;
// Traverse all processes one by one repeatedly
for (int i = 0 ; i < n; i++)
{
// If burst time of a process is greater than 0
// then only need to process further
if (rem_bt[i] > 0)
{
done = 0; // There is a pending process
if (rem_bt[i] > quantum)
{
// Increase the value of t i.e. shows
// how much time a process has been processed
t += quantum;
// Decrease the burst_time of current process
// by quantum
rem_bt[i] -= quantum;
}
// If burst time is smaller than or equal to
// quantum. Last cycle for this process
else
{
// Increase the value of t i.e. shows
// how much time a process has been processed
t = t + rem_bt[i];
// Waiting time is current time minus time
// used by this process
wt[i] = t - bt[i];
// As the process gets fully executed
// make its remaining burst time = 0
rem_bt[i] = 0;
}
}
}
// If all processes are done
if (done == 1)
break;
}
}
// Function to calculate turn around time
void findTurnAroundTime(int processes[], int n,
int bt[], int wt[], int tat[])
{
// calculating turnaround time by adding
// bt[i] + wt[i]
for (int i = 0; i < n ; i++)
tat[i] = bt[i] + wt[i];
}
// Function to calculate average time
void findavgTime(int processes[], int n, int bt[],
int quantum)
{
int wt[n], tat[n], total_wt = 0, total_tat = 0;
// Function to find waiting time of all processes
findWaitingTime(processes, n, bt, wt, quantum);
// Function to find turn around time for all processes
findTurnAroundTime(processes, n, bt, wt, tat);
// Display processes along with all details
printf("Processes Burst time Waiting time Turn around time\n");
// Calculate total waiting time and total turn
// around time
for (int i=0; i<n; i++)
{
total_wt = total_wt + wt[i];
total_tat = total_tat + tat[i];
printf(" %c\t\t%d\t %d\t\t%d\n",(char)(processes[i]+64),bt[i],wt[i],tat[i]);
}
printf("Average waiting time = %f",(float)total_wt/(float)n);
printf("\nAverage turn around time = %f",(float)total_tat / (float)n);
}
// Driver code
int main()
{
// process id's
int processes[10];
int n = 10;
// Burst time of all processes
int burst_time[10] = {16,2,11,6,1,9,4,14,1,8};
int i,j,pos,temp;
for(i=0;i<n;i++)
{
processes[i]=i+1; //contains process number
}
//sorting burst time in ascending order using selection sort
for(i=0;i<n;i++)
{
pos=i;
for(j=i+1;j<n;j++)
{
if(burst_time[j]<burst_time[pos])
pos=j;
}
temp=burst_time[i];
burst_time[i]=burst_time[pos];
burst_time[pos]=temp;
temp=processes[i];
processes[i]=processes[pos];
processes[pos]=temp;
}
printf("\nThe order of execution is:");
for(i=0;i<n;i++)
{
printf("\n%c",(char)(processes[i]+64));
}
// Time quantum
int quantum = 2;
findavgTime(processes, n, burst_time, quantum);
return 0;
}
)