require "bigdecimal"
a, b, c = gets.to_s.split.map{|i| BigDecimal(i) }

if a < 0
  a = -a
  b = -b
  c = -c
end

if a == 0 && b == 0
  puts c == 0 ? -1 : 0
elsif a == 0
  puts 1
  printf "%.15f\n", (-c/1.0/b)
else
  d = b ** 2 - 4 * a * c
  if d < 0
    puts 0
  elsif d == 0
    puts 1
    printf "%.15f\n", (-b/2.0/a)
    # ans = Rational( -b, 2 * a)
    # puts "1 #{ans.to_f}"
  else
    ans1 = (-b - d.sqrt(100)) / ( 2.0 * a )
    ans2 = (-b + d.sqrt(100)) / ( 2.0 * a )
    puts 2
    printf "%.15f\n", ans1
    printf "%.15f\n", ans2
    # puts "2 #{ans1.to_f} #{ans2.to_f}"
  end
end