n, b = read_line.split.map(&.to_u64)
if b == 1
  puts 0
  exit
end
if n == 0 || n.gcd(b) != 1
  puts "NaN"
  exit
end
n %= b
1.upto(b) do |i|
  if n * i % b == 1
    puts i
    exit
  end
end