output_description: Print the probability that a is odd. Your output will be considered correct
  when its absolute or relative error from the judge's output is at most
  10^{-6}.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: A, B = map(int, input().split())
  
  divisors = []
  for i in range(1, min(A, B) + 1):
      if A % i == 0 and B % i == 0:
          divisors.append(i)
  
  
  done = {}
  
  
  def is_coprime(a, b):
      if (a, b) in done:
          return done[a, b]
      if b == 1:
          return True
      for i in range(2, min(A, B)):
          if a % i == 0 and b % i == 0:
              done[(a, b)] = False
              return False
      done[(a, b)] = True
      return True
  
  
  def getMaxLen(sofar, divisors):
      if len(divisors) == 0:
          return len(sofar)
      curr_max = getMaxLen(sofar, divisors[1:])
      for i in range(len(divisors)):
          d = divisors[i]
          flag = False
          for s in sofar:
              if not is_coprime(d, s):
                  flag = True
                  break
          if flag:
              continue
          new = sofar.copy()
  
          new.append(d)
          curr_max = max(curr_max, getMaxLen(new, divisors[i + 1 :]))
      return curr_max
  
  
  print(getMaxLen([], divisors))
  
problem_description: Statement
  
  Given is an integer N.
  
  Takahashi chooses an integer a from the positive integers not greater than N
  with equal probability.
  
  Find the probability that a is odd.
samples: [{"input": "4", "output": "0.5000000000\n    \n\nThere are four positive integers not greater than 4: 1, 2, 3, and 4. Among\nthem, we have two odd numbers: 1 and 3. Thus, the answer is \\frac{2}{4} = 0.5.\n\n* * *"}, {"input": "5", "output": "0.6000000000\n    \n\n* * *"}, {"input": "1", "output": "1.0000000000"}]