How can quickly merge strings in Python

Question

I have strings like this:

strA = "Today is hot. My dog love hot dog, milk, and candy."
strB = "hot dog and bread"

I hope the output string like:

"Today is hot. My dog love hot dog and bread, milk, and candy."

not

"Today is hot dog and bread. My dog love hot dog, milk, and candy."

I tried to use str.find() but it's not suitable.

if strA.find(strB) != -1:    
    x = strA.find(strB)
    listA = list(strA)
    listA.insert(x, strB)
    output = ''.join(listA)

This may help [Insert some string into given string at given index in Python](https://stackoverflow.com/questions/4022827/insert-some-string-into-given-string-at-given-index-in-python) — Tek Nath Acharya, Jul 12 '19 at 08:24
@KlausD. I update my question, thanks! It want merging the most similar sentence. — Furry Bear, Jul 12 '19 at 08:30
@FurryBear, ok, what's the expected output for `"Today is hot. My dog love hot dog, milk. But my cat loves hot dog and fish"` ? — RomanPerekhrest, Jul 12 '19 at 08:33
this problem is very similar to [sequence alignment](https://en.wikipedia.org/wiki/Sequence_alignment) in bioinformatics. an aim there is to find the closest matching substring while allowing for mistakes. you could then use this match to do your insertion/replacement of text — Sam Mason, Jul 12 '19 at 12:15

score 0 · Answer 1 · answered Jul 12 '19 at 08:29

0

strA = "My dog love hot dog, milk, and candy."
strB = "dog and bread"

strA = strA.replace('dog,',strB);
print(strA);

this is not a dynamic solution. but can work for this problem

answered Jul 12 '19 at 08:29

Abhishek-Saini

733
7
11

sorry, my bad, i didn't notice that comma. – AcaNg Jul 12 '19 at 08:40
how about `strB = "hot dog and bread"` and `strA.replace("hot dog", strB)` ? – AcaNg Jul 12 '19 at 08:42

score 0 · Accepted Answer · answered Jul 15 '19 at 01:48

You can do a reverse lookup and return the best matched result.

strA = "Today is hot. My dog love hot dog, milk, and candy."
strB = "hot dog and bread"

def replace_method(string_a,string_b):
    s = string_b.split()
    for i in reversed(range(len(s)+1)):
        if " ".join(s[:i]) in string_a:
            return string_a.replace(" ".join(s[:i]),string_b)

print (replace_method(strA,strB))

Result:

Today is hot. My dog love hot dog and bread and cheese, milk, and candy.

How can quickly merge strings in Python

2 Answers2