A, B, C = gets.split.map(&:to_i)

if A == 0
  puts -1
else
  e = B ** 2 - 4 * A * C

  if e == 0
    puts 1
    puts "%.12f" % Rational(-B, 2 * A)
  elsif e < 0
    puts 0
  else
    puts 2
    puts "%.12f" % Rational(-B - Math.sqrt(e), 2 * A)
    puts "%.12f" % Rational(-B + Math.sqrt(e), 2 * A)
  end
end