# Python3 program for implementation of 
# RR scheduling 

# Function to find the waiting time 
# for all processes 
def findWaitingTime(processes, n, bt, 
						wt, quantum): 
	rem_bt = [0] * n

	# Copy the burst time into rt[] 
	for i in range(n): 
		rem_bt[i] = bt[i]
	t = 0 # Current time 

	# Keep traversing processes in round 
	# robin manner until all of them are
	# not done. 
	while(1):
		done = True

		# Traverse all processes one by
		# one repeatedly 
		for i in range(n):
			
			# If burst time of a process is greater 
			# than 0 then only need to process further 
			if (rem_bt[i] > 0) :
				done = False # 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 == True):
			break
			
# Function to calculate turn around time 
def findTurnAroundTime(processes, n, bt, wt, tat):
	
	# Calculating turnaround time 
	for i in range(n):
		tat[i] = bt[i] + wt[i] 


# Function to calculate average waiting 
# and turn-around times. 
def findavgTime(processes, n, bt, quantum): 
	wt = [0] * n
	tat = [0] * n 

	# 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 
	print("Processes Burst Time	 Waiting", 
					"Time Turn-Around Time")
	total_wt = 0
	total_tat = 0
	for i in range(n):

		total_wt = total_wt + wt[i] 
		total_tat = total_tat + tat[i] 
		print(" ", i + 1, "\t\t", bt[i], 
			"\t\t", wt[i], "\t\t", tat[i])

	print("\nAverage waiting time = %.5f "%(total_wt /n) )
	print("Average turn around time = %.5f "% (total_tat / n)) 
	
# Driver code 
if __name__ =="__main__":
	
	# Process id's 
	proc = [1, 2, 3]
	n = 3

	# Burst time of all processes 
	burst_time = [10, 5, 8] 

	# Time quantum 
	quantum = 2; 
	findavgTime(proc, n, burst_time, quantum)

# This code is contributed by
# Shubham Singh(SHUBHAMSINGH10)