module SeatedInClassroom
  def solve(n, m)
    rnd = n / 4
    r = n % 4
    if r > 0
      vc = rnd * 4 + 8 - r
      if vc < m
        rnd += (m - vc + 7) / 8
      end
      rnd += 1
    else
      vc = rnd * 4
      if vc < m
        rnd += (m - vc + 7) / 8
      end
    end
    rnd
  end

  module_function :solve
end

t = gets.chomp.to_i
t.times do
  n, m = gets.chomp.split(/\s+/).map(&:to_i)
  puts SeatedInClassroom.solve(n, m)
end