From 259b296d53750540ce61cbdd0143e44bcc347389 Mon Sep 17 00:00:00 2001 From: katarzynakaz Date: Sat, 18 Apr 2026 03:14:56 +0100 Subject: [PATCH 1/2] sort strs upfront --- .../common_prefix/common_prefix.py | 20 ++++++++++++++----- 1 file changed, 15 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..f58f135 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 +7,20 @@ 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 "" 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 + + sorted_strings = sorted(strings) + + 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 @@ -22,3 +30,5 @@ def find_common_prefix(left: str, right: str) -> str: if left[i] != right[i]: return left[:i] return left[:min_length] + + From 6f65175a59d6ad7ae179bfcec2f9efe5c14f62a2 Mon Sep 17 00:00:00 2001 From: katarzynakaz Date: Sat, 18 Apr 2026 03:33:51 +0100 Subject: [PATCH 2/2] add set to count_letters --- .../count_letters/count_letters.py | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 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..3329b32 100644 --- a/Sprint-2/improve_with_precomputing/count_letters/count_letters.py +++ b/Sprint-2/improve_with_precomputing/count_letters/count_letters.py @@ -2,13 +2,15 @@ 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() - for letter in s: - if is_upper_case(letter): - if letter.lower() not in s: - only_upper.add(letter) - return len(only_upper) + present_chars = set(s) + only_upper_count = 0 + for char in present_chars: + if char.isupper(): + if char.lower() not in present_chars: + only_upper_count += 1 + + return only_upper_count def is_upper_case(letter: str) -> bool: return letter == letter.upper()