old_contents: """
  Source : https://oj.leetcode.com/problems/excel-sheet-column-number/
  Author : Changxi Wu
  Date   : 2015-01-21
  
  Given a column title as appear in an Excel sheet, return its corresponding column number.
  
  For example:
      1 -> A
      2 -> B
      3 -> C
      ...
      26 -> Z
      27 -> AA
      28 -> AB
  """
  
  # @return a string
  def convertToTitle(num):
  
  
  if __name__ == '__main__':
      test = [1:'A', 2:'B', 3:'C', 26:'Z', 27:'AA', 28:'AB']
  
new_contents: """
  Source : https://oj.leetcode.com/problems/excel-sheet-column-number/
  Author : Changxi Wu
  Date   : 2015-01-21
  
  Given a column title as appear in an Excel sheet, return its corresponding column number.
  
  For example:
      1 -> A
      2 -> B
      3 -> C
      ...
      26 -> Z
      27 -> AA
      28 -> AB
      732 -> ABC
  """
  
  # @return a string
  def convertToTitle(num):
      remainders = []
      quotient = num
      while quotient > 26:
          remainder = quotient%26 or 26
          quotient = (quotient-remainder)/26
          remainders.append(remainder)
      remainders.append(quotient)
      chars = []
      for i in reversed(remainders):
          chars.append(chr(i+ord('A')-1))
      return ''.join(chars)
  
  if __name__ == '__main__':
      test = {1:'A', 2:'B', 3:'C', 26:'Z', 27:'AA', 28:'AB', 52:'AZ', 731:'ABC'}
      for k,v in test.iteritems():
          output = convertToTitle(k)
          if v != output:
              print 'Input:', k
              print 'Output:', output
              print 'Expected:', v
  
subject: Add solution for excel sheet column title