read_line.to_i.times do
  puts solve()
end

def solve
  n = read_line.to_i
  a = read_line.split.map(&.to_i64)
  vs = a[1..].each.map do |v|
    while v != 0 && v < 1_000_000_000i64
      v *= 10i64
    end
    v
  end.select { |v| v > 0 }.to_a
  return 1 if vs.empty?
  gcd = vs.reduce(10_000_000_000i64) { |a, v| a.gcd(v) }
  puts vs
  puts gcd
  10_000_000_000i64 // gcd
end