如何在两个字符串中找到匹配的单词？

Question

我有两个字符串

My name is Bogdan 和 Bogdan and I am from Russia

我需要从这个字符串中获取单词 Bogdan。我总是知道第一句的结尾 == 第二句的开头。

如何找到重叠部分。

我的解决方案returns 相似字符

res = list(set('My name is Bogdan').intersection(set('Bogdan and i am from Russia')))
print(res)

Returns

['i', 'n', 'g', 'm', ' ', 's', 'B', 'a', 'd', 'o']

Answer 1

您首先将两个字符串最大程度地重叠，然后通过减少重叠进行迭代：

def find_overlap(s1, s2):
    for i in range(len(s1)):
        test1, test2 = s1[i:], s2[:len(s1) - i]
        if test1 == test2:
            return test1

s1, s2 = "My name is Bogdan", "Bogdan and I am from Russia"
find_overlap(s1, s2)
# 'Bogdan'
s1, s2 = "mynameisbogdan", "bogdanand"
find_overlap(s1, s2)
# 'bogdan'

如您所见，如果两个字符串不包含空格，这也有效。

这具有 O(n) 运行时间，但如果您首先确定两个字符串中哪个更短，则可以减少到 O(min(n, m))。

如果您希望找到的字符串比两个字符串中最短的字符串短得多，您可以将其设置为偶数 O(k)，其中 k 是要查找的字符串的长度，从最小值开始重叠：

def find_overlap(s1, s2):
    for i in range(1, len(s1) + 1):
        if i == len(s2):
            return None
        test1, test2 = s1[-i:], s2[:i]
        if test1 == test2:
            return test1

Answer 2

可以使用集合交集

l1="My name is Bogdan"
l2="Bogdan and I am from Russia"
print(set(l1.split())&set(l2.split())) # set('Bogdan')

列表理解

l1="My name is Bogdan"
l2="Bogdan and I am from Russia"
[i for i in l1.split() if i in l2.split()] ['Bogdan']

Answer 3

其他选项，带 for 循环：

def shared_words(s1, s2):
  res = []
  l_s1, l_s2 = set(s1.split()), set(s2.split())
  for ss1 in l_s1:
    if ss1 in l_s2: res.append(ss1)
  return res

应用于字符串：

s1 = "My name is Bogdan"
s2 = "Bogdan and I am from Russia"
print(shared_words(s1, s2)) #=> ['Bogdan']

或者，使用正则表达式只拆分单词：

import re

def shared_words(s1, s2):
  res = []
  l_s1, l_s2 = set(re.findall(r'\w+',s1)), set(re.findall(r'\w+',s2))
  for ss1 in l_s1:
    if ss1 in l_s2: res.append(ss1)
  return res

获得：

s1 = "My name is Bogdan, I am here"
s2 = "Bogdan and I am from Russia."
print(shared_words(s1, s2)) #=> ['Bogdan', 'I', 'am']

如何在两个字符串中找到匹配的单词？

How to find a match of words in two strings?

python

arrays

string

list

overlap