T = gets.to_i

def solver(a, b)
  ans = []
  la = a.bit_length
  lb = b.bit_length

  l = [*0...lb].reverse.find { |i| a[i] != b[i] }
  idx = 0

  while a[l] == 0
    if a[idx] == 1
      ans << 2.pow(idx)
      a += 2.pow(idx)
    end

    idx += 1
  end

  (lb - 2).downto(0) do |i|
    if b[i] == 1 && a[i] == 0
      ans << 2.pow(i)
      a += 2.pow(i)
    end
  end

  puts ans.size
  puts ans.join(' ')
end

T.times do
  a, b = gets.split.map(&:to_i)

  solver(a, b)
end