output_description: If at least x operations are required to withdraw exactly N yen in total,
  print x.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: N = int(input())
  list1 = [0] * (N + 1)
  for i in range(1, N + 1):
      list2 = [list1[i - 1]]
      l = list2.append
      if i >= 6:
          l(list1[i - 6])
          if i >= 9:
              l(list1[i - 9])
              if i >= 36:
                  l(list1[i - 36])
                  if i >= 81:
                      l(list1[i - 81])
                      if i >= 216:
                          l(list1[i - 216])
                          if i >= 729:
                              l(list1[i - 729])
                              if i >= 1296:
                                  l(list1[i - 1296])
                                  if i >= 6561:
                                      l(list1[i - 6561])
                                      if i >= 7776:
                                          l(list1[i - 7776])
                                          if i >= 46656:
                                              l(list1[i - 46656])
                                              if i >= 59049:
                                                  l(list1[i - 59049])
      list1[i] = min(list2) + 1
  print(list1[N])
  
problem_description: Statement
  
  To make it difficult to withdraw money, a certain bank allows its customers to
  withdraw only one of the following amounts in one operation:
  
    * 1 yen (the currency of Japan)
  
    * 6 yen, 6^2(=36) yen, 6^3(=216) yen, ...
  
    * 9 yen, 9^2(=81) yen, 9^3(=729) yen, ...
  
  At least how many operations are required to withdraw exactly N yen in total?
  
  It is not allowed to re-deposit the money you withdrew.
samples: [{"input": "127", "output": "4\n    \n\nBy withdrawing 1 yen, 9 yen, 36(=6^2) yen and 81(=9^2) yen, we can withdraw\n127 yen in four operations.\n\n* * *"}, {"input": "3", "output": "3\n    \n\nBy withdrawing 1 yen three times, we can withdraw 3 yen in three operations.\n\n* * *"}, {"input": "44852", "output": "16"}]