a,b,c=map(int,input().split())
if a==0 and b==0 and c==0:
	print(-1)
elif a==0 and b==0:
	print(0)
elif a==0:
	print(1)
	print(-c/b)
else:
	tmp=-c+b**2/(4*a)
	tmp/=a
	if -c+b**2/(4*a)<0:
		print(0)
	elif tmp==0:
		print(1)
		print(-b/(2*a))
	else:
		print(2)
		print(-tmp**.5-b/(2*a))
		print(tmp**.5-b/(2*a))