#mini quiz oct 30 solution
#http://cs.widener.edu/~yanako/html/courses/Fall20/csci151/30.html
def final_price(num_items):
	total=0
	for i in range(num_items):
		price=float(input("enter price "))
		total=total+price
	print("total before coupon", format(total, ".2f"))
	disc2=total*20/100
	if(total>=30):
		disc1=10
		if(disc1>disc2):
			final=total-10
		else:
			final=total-disc2
	else:
		final=total-disc2
	return final	
def main():
	num_items=int(input("enter number of items "))
	result=final_price(num_items)
	print("final price", format(result, ".2f"))
main()