def lscan; gets.split.map(&:to_r); end
a,b,c = lscan
if a == 0
  if b == 0
    if c == 0 
      p -1
    else
      p 0
    end
    exit
  end
  p 1
  h = -c/b
  printf "%.15f\n", h
  exit
end
d = b*b-4*a*c
z = -b/2/a
if d < 0
  p 0
elsif d == 0
  p 1
  printf "%.15f\n", z
else
  # 2az + b = 0
  p 2
  printf "%.15f\n", (-1e99..z.to_f).bsearch{|x| a*x*x+b*x+c < 0}
  printf "%.15f\n", (z.to_f..1e99).bsearch{|x| a*x*x+b*x+c > 0}
  # printf "%.15f\n", z-Math.sqrt(d)/2/a.abs
  # printf "%.15f\n", z+Math.sqrt(d)/2/a.abs
end