import sys
import math

a, b, c = map(int, input().split())

if a == 0 and b == 0 and c == 0:
  print(-1)
  sys.exit()

if a == 0 and b == 0:
  print(0)
  sys.exit()

if a == 0:
  print(1)
  print(-c / b)
  sys.exit()

D = b**2-4*a*c
if D < 0:
  print(0)
  sys.exit()

if D == 0:
  print(1)
  print(-b / (2*a))
  sys.exit()

print(2)
print((-b - math.sqrt(D)) / (2*a))
print((-b + math.sqrt(D)) / (2*a))