#Write a program that first reads the number of students in the class, 
#then reads the grade for each student. The program finds the average grade in 
#the class. 

#this is a counter-controlled repetition.
#the loop will iterate size times

size=int(input("size of the class - number of students in the class "))
i=1
sum_grades=0
if(size>0):
	print("enter grades for", size, "students")
	while(i<=size): 
		#i=1, 2, ....till i=size the statement will be True and 
		#the loop will iterate size times
		#print("enter grade for student",i)
		grade=int(input(""))
		sum_grades=sum_grades+grade
		i=i+1

	#if(size>0):
	print("average grade", sum_grades/size)
	#else:
	#print("empty class or invalid input")
else:
	print("empty class or invalid input")