819. 最常见的单词

 1 import re
 2 
 3 class Solution(object):
 4     def mostCommonWord(self, paragraph, banned):
 5         """
 6         :type paragraph: str
 7         :type banned: List[str]
 8         :rtype: str
 9         """
10         # 段落中的字母全部转成小写
11         paragraph = paragraph.lower()
12         # 用多种标点符号和空格分割段落
13         listpara = re.split(r‘[!?\‘.;,\s]\s*‘, paragraph)
14         # print(listpara)
15         # 计数器
16         num = 0
17         # 返回值，即出现次数最多，同时不在禁用列表中的单词
18         ans = ""
19         for i, ch in enumerate(listpara):
20             if ch not in banned and listpara.count(ch) > num:
21                 num = listpara.count(ch)
22                 ans = ch
23         return ans
24 
25 
26 if __name__ == ‘__main__‘:
27     solution = Solution()
28     print(solution.mostCommonWord("Bob hit a ball, the hit BALL flew far after it was hit.", ["hit"]))
29     print(solution.mostCommonWord("a, a, a, a, b,b,b,c, c", ["a"]))