# Problem 3
# 15.0/15.0 points (graded)
# 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
# Note: This problem may be 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.

lstring = s[0]
cstring = s[0]

for char in s[1::]:
    if char >= cstring[-1]:
        cstring += char
        if len(cstring) > len(lstring):
            lstring = cstring
    else:
        cstring = char
print(lstring)
