Update match_word_pattern.py Fixes #9943

backtracking/match_word_pattern.py

@@ -12,21 +12,26 @@ def match_word_pattern(pattern: str, input_string: str) -> bool:
  >>> match_word_pattern("xyx", "PythonRubyPython")
  True
 
- >>> match_word_pattern("GG", "PythonJavaPython")
- False
- """
+ >>> match_word_pattern("", "")
+ True
 
- def backtrack(pattern_index: int, str_index: int) -> bool:
- """
- >>> backtrack(0, 0)
- True
+ >>> match_word_pattern("a", "abc")
+ True
 
- >>> backtrack(0, 1)
- True
+ >>> match_word_pattern("ab", "abab")
+ True
+
+ >>> match_word_pattern("ab", "a b")
+ True
 
- >>> backtrack(0, 4)
- False
- """
+ >>> match_word_pattern("abc", "xyzpqrstu")
+ True
+
+ >>> match_word_pattern("abcd", "xyzaaabcd")
+ True
+ """
+
+ def backtrack(pattern_index: int, str_index: int) -> bool:
  if pattern_index == len(pattern) and str_index == len(input_string):
  return True
  if pattern_index == len(pattern) or str_index == len(input_string):
@@ -40,14 +45,16 @@ def backtrack(pattern_index: int, str_index: int) -> bool:
  return False
  for end in range(str_index + 1, len(input_string) + 1):
  substr = input_string[str_index:end]
- if substr in str_map:
- continue
- pattern_map[char] = substr
- str_map[substr] = char
- if backtrack(pattern_index + 1, end):
- return True
- del pattern_map[char]
- del str_map[substr]
+ if substr in str_map and str_map[substr] == char:
+ if backtrack(pattern_index + 1, end):
+ return True
+ elif substr not in str_map.values():
+ pattern_map[char] = substr
+ str_map[substr] = char
+ if backtrack(pattern_index + 1, end):
+ return True
+ del pattern_map[char]
+ del str_map[substr]
  return False
 
  pattern_map: dict[str, str] = {}