Python如何判断两个及以上字符串是否拥有指定数量的共同单词

实现逻辑 #

• 先清洗输入字符串：剔除所有标点符号，拆分出独立单词
• 单词匹配不区分大小写，同时支持保留原单词的书写格式
• 求多个字符串的单词交集，判断长度是否≥3后输出结果

双字符串匹配代码 #

import string

def get_common_words(str1, str2):
    # 字符串清洗处理：返回{小写单词: 原格式单词}映射
    def process_string(s):
        # 去除所有标点
        remove_punct = str.maketrans('', '', string.punctuation)
        cleaned_s = s.translate(remove_punct)
        word_list = cleaned_s.split()
        return {word.lower(): word for word in word_list}
    
    words_map1 = process_string(str1)
    words_map2 = process_string(str2)
    # 取共同单词的小写key
    common_lower_keys = words_map1.keys() & words_map2.keys()
    # 按第一个字符串的出现顺序返回原格式共同单词
    common_words = [word for word in words_map1.values() if word.lower() in common_lower_keys]
    return common_words

# 示例测试
string1 = "Password age (minimum) is set to 60"
string2 = "age of password is set to 60 or less!"

common_words = get_common_words(string1, string2)
if len(common_words) >= 3:
    print("string1 & string2 have 3 or more words in common:\n")
    print(common_words)
else:
    print("string1 & string2 have less than 3 words in common")

运行后输出结果和要求一致：

string1 & string2 have 3 or more words in common:

['Password', 'age', 'is', 'set', 'to', '60']

多字符串批量匹配拓展 #

如果需要同时匹配N个字符串的共同单词，可以用以下版本：

import string
from functools import reduce

def get_multi_str_common(str_list):
    def process_string(s):
        remove_punct = str.maketrans('', '', string.punctuation)
        cleaned_s = s.translate(remove_punct)
        word_list = cleaned_s.split()
        return {word.lower(): word for word in word_list}
    
    processed_maps = [process_string(s) for s in str_list]
    # 求所有字符串的共同单词key
    common_keys = reduce(lambda a, b: a.keys() & b.keys(), processed_maps)
    common_words = [word for word in processed_maps[0].values() if word.lower() in common_keys]
    return common_words

# 多字符串测试
test_strs = [
    "Password age (minimum) is set to 60",
    "age of password is set to 60 or less!",
    "your password age should be set to 60"
]
common = get_multi_str_common(test_strs)
if len(common) >= 3:
    print(f"所有输入字符串共有{len(common)}个共同单词，满足≥3要求：\n")
    print(common)

内容的提问来源于stack exchange，提问作者IRezzet