29 lines
921 B
Python
29 lines
921 B
Python
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# Based on https://github.com/AllAlgorithms, python/algorithms/math/longest_substring.py
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# Create an algorithm that prints the longest substring of s in which
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# the letters occur in alphabetical order. For example, if
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# s = 'azcbobobegghakl', then your program should print:
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# Longest substring in alphabetical order is: beggh
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# In the case of ties, print the first substring.
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# For example, if s = 'abcbcd', then your program should print:
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# Longest substring in alphabetical order is: abc
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def longest_sorted_substr(s: str) -> str:
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count = 0
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max_count = 0
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end_position = 0
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for char in range(len(s) - 1):
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if (s[char] <= s[char + 1]):
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count += 1
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if count > max_count:
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max_count = count
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end_position = char + 1
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else:
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count = 0
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start_position = end_position - max_count
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return s[start_position:end_position+1]
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