new_contents: '''
  ALPHABETICAL SUBSTRINGS  (15.0/15.0 points)
  Assume s is a string of lower case characters.
  
  Write a program that prints the longest substring of s in which the letters occur in alphabetical order. 
  For example, if s = 'azcbobobegghakl', then your program should print
  
  Longest substring in alphabetical order is: beggh
  
  
  In the case of ties, print the first substring. For example, if s = 'abcbcd', then your program should print
  
  Longest substring in alphabetical order is: abc
  
  For problems such as these, do not include raw_input statements or define the variable s in any way. 
  Our automating testing will provide a value of s for you - 
  so the code you submit in the following box should assume s is already defined. 
  If you are confused by this instruction, please review L4 Problems 10 and 11 before you begin this problem set.
  
  Note: This problem is fairly challenging. We encourage you to work smart. 
  If you've spent more than a few hours on this problem, we suggest that you move on to a different part of the course. 
  If you have time, come back to this problem after you've had a break and cleared your head.
  
  '''
  first,last = 0,0
  s = 'azcbobobegghakl'
  for letter in range(len(s)+1):
      if  letter !=(len(s)) and ord(s[letter])>= ord(s[letter-1]):
              last = letter
      else:
              long_string.append(s[first:last+1])
              first,last = letter, letter
  print "Longest substring in alphabetical order is: "  + max(long_string, key=len)
  
  
subject: Create problem3.py