From 394b46d6cea53bc62d1830eecb7da5b347a354f1 Mon Sep 17 00:00:00 2001 From: Craig D'Silva Date: Wed, 1 Jul 2026 11:50:16 +0100 Subject: [PATCH 1/2] common_prefix --- .../common_prefix/common_prefix.py | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/Sprint-2/improve_with_precomputing/common_prefix/common_prefix.py b/Sprint-2/improve_with_precomputing/common_prefix/common_prefix.py index f4839e7..2d2d369 100644 --- a/Sprint-2/improve_with_precomputing/common_prefix/common_prefix.py +++ b/Sprint-2/improve_with_precomputing/common_prefix/common_prefix.py @@ -7,12 +7,17 @@ def find_longest_common_prefix(strings: List[str]): In the event that an empty list, a list containing one string, or a list of strings with no common prefixes is passed, the empty string will be returned. """ + if len(strings) < 2: + return "" + + sorted_strings = sorted(strings) longest = "" - for string_index, string in enumerate(strings): - for other_string in strings[string_index+1:]: - common = find_common_prefix(string, other_string) - if len(common) > len(longest): - longest = common + + for i in range(len(sorted_strings) - 1): + common = find_common_prefix(sorted_strings[i], sorted_strings[i + 1]) + if len(common) > len(longest): + longest = common + return longest From 3e1b1d51aeb026dacfe8760cc5ec91e0510de3c0 Mon Sep 17 00:00:00 2001 From: Craig D'Silva Date: Wed, 1 Jul 2026 15:03:21 +0100 Subject: [PATCH 2/2] count_letters --- .../count_letters/count_letters.py | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Sprint-2/improve_with_precomputing/count_letters/count_letters.py b/Sprint-2/improve_with_precomputing/count_letters/count_letters.py index 62c3ec0..ee4d423 100644 --- a/Sprint-2/improve_with_precomputing/count_letters/count_letters.py +++ b/Sprint-2/improve_with_precomputing/count_letters/count_letters.py @@ -3,10 +3,10 @@ def count_letters(s: str) -> int: count_letters returns the number of letters which only occur in upper case in the passed string. """ only_upper = set() + lowercase_letters = {letter for letter in s if not is_upper_case(letter)} for letter in s: - if is_upper_case(letter): - if letter.lower() not in s: - only_upper.add(letter) + if letter.lower() not in lowercase_letters: + only_upper.add(letter) return len(only_upper)