output_description: Print the answer to Roger's question as a string consisting of lowercase
  English letters.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
attempt: import sys
  
  
  def input():
      return sys.stdin.readline().strip()
  
  
  def main():
      n = int(input())
      con = 0
      for i in range(10):
          con += 26 ** (i + 1)
          if n <= con:
              num = i + 1
              break
      b = n - 26 ** (num - 1) + 1
      c = n - 26 ** (num - 1)
      if num == 1:
          a = b % 26
          if a == 1:
              ans = "a"
          if a == 2:
              ans = "b"
          if a == 3:
              ans = "c"
          if a == 4:
              ans = "d"
          if a == 5:
              ans = "e"
          if a == 6:
              ans = "f"
          if a == 7:
              ans = "g"
          if a == 8:
              ans = "h"
          if a == 9:
              ans = "i"
          if a == 10:
              ans = "j"
          if a == 11:
              ans = "k"
          if a == 12:
              ans = "l"
          if a == 13:
              ans = "m"
          if a == 14:
              ans = "n"
          if a == 15:
              ans = "o"
          if a == 16:
              ans = "p"
          if a == 17:
              ans = "q"
          if a == 18:
              ans = "r"
          if a == 19:
              ans = "s"
          if a == 20:
              ans = "t"
          if a == 21:
              ans = "u"
          if a == 22:
              ans = "v"
          if a == 23:
              ans = "w"
          if a == 24:
              ans = "x"
          if a == 25:
              ans = "y"
          if a == 0:
              ans = "z"
          print(ans, end="")
          return
  
      for i in range(num):
          if i == num - 1:
              if c == 1:
                  ans = "a"
              elif c == 2:
                  ans = "b"
              elif c == 3:
                  ans = "c"
              elif c == 4:
                  ans = "d"
              elif c == 5:
                  ans = "e"
              elif c == 6:
                  ans = "f"
              elif c == 7:
                  ans = "g"
              elif c == 8:
                  ans = "h"
              elif c == 9:
                  ans = "i"
              elif c == 10:
                  ans = "j"
              elif c == 11:
                  ans = "k"
              elif c == 12:
                  ans = "l"
              elif c == 13:
                  ans = "m"
              elif c == 14:
                  ans = "n"
              elif c == 15:
                  ans = "o"
              elif c == 16:
                  ans = "p"
              elif c == 17:
                  ans = "q"
              elif c == 18:
                  ans = "r"
              elif c == 19:
                  ans = "s"
              elif c == 20:
                  ans = "t"
              elif c == 21:
                  ans = "u"
              elif c == 22:
                  ans = "v"
              elif c == 23:
                  ans = "w"
              elif c == 24:
                  ans = "x"
              elif c == 25:
                  ans = "y"
              else:
                  ans = "z"
              print(ans, end="")
          a = c // (26 ** (num - 1 - i))
          c = c % (26 ** (num - 1 - i))
          if c == 0:
              c = 26 ** (num - 1 - i)
          if i < num - 1:
              if i != 0:
                  if a == 0:
                      a = 25
                  else:
                      a -= 1
              if a == 0:
                  ans = "a"
              elif a == 1:
                  ans = "b"
              elif a == 2:
                  ans = "c"
              elif a == 3:
                  ans = "d"
              elif a == 4:
                  ans = "e"
              elif a == 5:
                  ans = "f"
              elif a == 6:
                  ans = "g"
              elif a == 7:
                  ans = "h"
              elif a == 8:
                  ans = "i"
              elif a == 9:
                  ans = "j"
              elif a == 10:
                  ans = "k"
              elif a == 11:
                  ans = "l"
              elif a == 12:
                  ans = "m"
              elif a == 13:
                  ans = "n"
              elif a == 14:
                  ans = "o"
              elif a == 15:
                  ans = "p"
              elif a == 16:
                  ans = "q"
              elif a == 17:
                  ans = "r"
              elif a == 18:
                  ans = "s"
              elif a == 19:
                  ans = "t"
              elif a == 20:
                  ans = "u"
              elif a == 21:
                  ans = "v"
              elif a == 22:
                  ans = "w"
              elif a == 23:
                  ans = "x"
              elif a == 24:
                  ans = "y"
              elif a == 25:
                  ans = "z"
              print(ans, end="")
  
  
  main()
  
problem_description: Statement
  
  1000000000000001 dogs suddenly appeared under the roof of Roger's house, all
  of which he decided to keep. The dogs had been numbered 1 through
  1000000000000001, but he gave them new names, as follows:
  
    * the dogs numbered 1,2,\cdots,26 were respectively given the names `a`, `b`, ..., `z`;
    * the dogs numbered 27,28,29,\cdots,701,702  were respectively given the names `aa`, `ab`, `ac`, ..., `zy`, `zz`;
    * the dogs numbered 703,704,705,\cdots,18277,18278  were respectively given the names `aaa`, `aab`, `aac`, ..., `zzy`, `zzz`;
    * the dogs numbered 18279,18280,18281,\cdots,475253,475254  were respectively given the names `aaaa`, `aaab`, `aaac`, ..., `zzzy`, `zzzz`;
    * the dogs numbered 475255,475256,\cdots  were respectively given the names `aaaaa`, `aaaab`, ...;
    * and so on.
  
  To sum it up, the dogs numbered 1, 2, \cdots were respectively given the
  following names:
  
  `a`, `b`, ..., `z`, `aa`, `ab`, ..., `az`, `ba`, `bb`, ..., `bz`, ..., `za`,
  `zb`, ..., `zz`, `aaa`, `aab`, ..., `aaz`, `aba`, `abb`, ..., `abz`, ...,
  `zzz`, `aaaa`, ...
  
  Now, Roger asks you:
  
  "What is the name for the dog numbered N?"
samples: [{"input": "2", "output": "b\n    \n\n* * *"}, {"input": "27", "output": "aa\n    \n\n* * *"}, {"input": "123456789", "output": "jjddja"}]