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[pre-commit.ci] auto fixes from pre-commit.com hooks

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pre-commit-ci[bot] 2024-10-17 21:20:00 +00:00
parent 00b17c4c7c
commit 7fc42c79f0
1 changed files with 26 additions and 28 deletions
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42
strings/min_window_substring.py
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@ -26,12 +26,11 @@ def min_window(search_str: str, target_letters: str) -> str:
target_count = len(target_letters) target_count = len(target_letters)
search_len = len(search_str) search_len = len(search_str)
# Return if not possible due to string lengths.
#Return if not possible due to string lengths. if search_len < target_count:
if (search_len < target_count):
return "" return ""
#Build dictionary with counts for each letter in target_letters # Build dictionary with counts for each letter in target_letters
char_dict = {} char_dict = {}
for ch in target_letters: for ch in target_letters:
if ch not in char_dict: if ch not in char_dict:
@ -39,49 +38,48 @@ def min_window(search_str: str, target_letters: str) -> str:
else: else:
char_dict[ch] += 1 char_dict[ch] += 1
#Initialize window # Initialize window
window_start = 0 window_start = 0
window_end = 0 window_end = 0
exists = False exists = False
min_window_len = search_len + 1 min_window_len = search_len + 1
#Start sliding window algorithm # Start sliding window algorithm
while(window_end < search_len): while window_end < search_len:
# Slide window end right until all search characters are contained
#Slide window end right until all search characters are contained while target_count > 0 and window_end < search_len:
while(target_count > 0 and window_end < search_len):
cur = search_str[window_end] cur = search_str[window_end]
if cur in char_dict: if cur in char_dict:
char_dict[cur] -= 1 char_dict[cur] -= 1
if (char_dict[cur] >= 0): if char_dict[cur] >= 0:
target_count -= 1 target_count -= 1
window_end += 1 window_end += 1
temp = window_end - window_start temp = window_end - window_start
#Check if window is the smallest found so far # Check if window is the smallest found so far
if (target_count == 0 and temp < min_window_len): if target_count == 0 and temp < min_window_len:
min_window = [window_start,window_end] min_window = [window_start, window_end]
exists = True exists = True
min_window_len = temp min_window_len = temp
#Slide window start right until a search character exits the window # Slide window start right until a search character exits the window
while(target_count == 0 and window_start < window_end): while target_count == 0 and window_start < window_end:
cur = search_str[window_start] cur = search_str[window_start]
window_start += 1 window_start += 1
if cur in char_dict: if cur in char_dict:
char_dict[cur] += 1 char_dict[cur] += 1
if (char_dict[cur] > 0): if char_dict[cur] > 0:
break break
temp = window_end - window_start + 1 temp = window_end - window_start + 1
#Check if window is the smallest found so far # Check if window is the smallest found so far
if (temp < min_window_len and target_count == 0): if temp < min_window_len and target_count == 0:
min_window = [window_start-1,window_end] min_window = [window_start - 1, window_end]
min_window_len = temp min_window_len = temp
target_count = 1 target_count = 1
if (exists): if exists:
return search_str[min_window[0]:min_window[1]] return search_str[min_window[0] : min_window[1]]
else: else:
return "" return ""