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:
       A -> 1
       B -> 2
       C -> 3
       ...
       Z -> 26
       AA -> 27
       AB -> 28 
  
  """
  
  
  def titleToNumber(s):
      # @praram s, a string
      # @return an integer
      result = 0
      length = len(s)
      for i, c in enumerate(s):
          if length == 1:
              result += (ord(c)-ord('A')+1)
          else:
              result += (ord(c)-ord('A')+1)*(26**(length-i-1))
      return result 
  
      
  
  if __name__ == '__main__':
      test = {'A':1, 'B':2, 'C':3, 'D':4, 'AA':27, 'AB':28, 'ABC':731}
      
      for s in test.keys():
          result = titleToNumber(s)
          if result != test[s]:
              print 'Input: ', s
              print 'Output:', result
              print 'Expected:', test[s]
  
subject: Add solution for excel sheet column number