text.find or None clear solution for Between Markers by StefanPochmann - python coding challenges

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text.find or None solution in Clear category for Between Markers by StefanPochmann

def between_markers(text: str, begin: str, end: str) -> str:
    start = text.find(begin) + len(begin) if begin in text else None
    stop = text.find(end) if end in text else None
    return text[start:stop]

Nov. 13, 2017

Comments:

salaheddineghamri on Jan. 26, 2018, 10:05 p.m.
Easy, clear and logical.

SathishBabu on March 25, 2018, 9:19 p.m.
thanks for clear solution

Cocoolanu on April 12, 2018, 10:11 a.m.
Cool, Stefan. You come to Checkio. Waiting for your more best solutions.

KumaraGade on April 22, 2018, 2:15 p.m.
I got it after writing 10 lines, you are awesome. Can you suggest any books or tutorials? thanks

Marcelo_Ozorio on May 29, 2018, 2:42 p.m.
I can I make easy things so hard? Very nice.

XueliJi on June 25, 2018, 3:17 a.m.
hi, i have a question about the answer. i can't understand why your code can work on example 2 whose begin marker is the same as end marker, how it can find the right index of stop?

zx1989031 on July 11, 2018, 7:40 a.m.
他是查找开始字符出现的位置，如果开始字符存，会返回开始字符所在key，并加上开始字符的长度就是找查找的内容的key的位置。如果开始字符不存，则返回None. text字符用list来取值时我想因该会自动将None转换为0. 同理结束字符也是这样工作的 stop = text.find(end) if begin in text else len(text)

veky on Sept. 16, 2018, 12:25 a.m.
<blockquote> But there are a few important conditions: * The initial and final markers are always different. </blockquote> So I'm not quite sure what are you referring to.

venya.e on July 23, 2018, 10:51 a.m.
Awesome!

PatinaHo on Aug. 3, 2018, 9:33 a.m.
I didn't know that you can place None when slicing! Thanks :)

Atilla_Misra on Aug. 11, 2018, 11:48 a.m.
<ul> <li>1</li> </ul>

GlulkAlex on Nov. 14, 2022, 4:13 p.m.
Same here :) <pre class='brush: python'>>>> "text"[None:None] 'text' </pre>

igor4672 on Jan. 10, 2024, 9:30 a.m.
same

chchun on Sept. 9, 2018, 10:45 a.m.
Hi I have question. In this case . between_markers("<head><title>My new</title> site</title></head>",<title>","</title>") The answer is 1. My new</title> site or 2. My new

koborC on Nov. 15, 2020, 9:29 a.m.
See the last line of the description... :) <blockquote> Precondition: can't be more than one final marker and can't be more than one initial. Marker can't be an empty string </blockquote>

alekseykonotop on Sept. 15, 2018, 7:19 p.m.
Super-Duper!

ahahawys on Sept. 16, 2018, 11:02 a.m.
hi Stefan! I found you in Leetcode and I really love your coding style. What a surprise seeing you here :-)

jcs42 on Sept. 27, 2018, 12:19 p.m.
very clear and very python

pumacens_64305eb2e37c43308c6c7 on Oct. 18, 2018, 11:09 p.m.
Subarashi!

WerkaRadzi on Nov. 4, 2018, 9:22 a.m.
Nice

DreadBeard on Nov. 12, 2018, 1:08 p.m.
Way more elegant than my solution however it fails to fulfill one of the exercise requirements: <ul> <li>If the initial and final markers are missing then simply return the whole string.</li> </ul> Could be fixed like this: <pre class='brush: python'>def between_markers(text: str, begin: str='', end: str='') -> str: if begin == '' and end == '': return text start = text.find(begin) + len(begin) if begin in text else None stop = text.find(end) if end in text else None return text[start:stop] </pre>

Idletuner on Jan. 12, 2019, 7:13 p.m.
Hmm, for me the solution, provided by Stefan worked fine for all exercises. If markers are missing at all, the "return text[start:stop]" will result in "return text[None:None]". text[None:None] will result in the whole string. Amazing.

thoufeeque.rafique on Jan. 18, 2022, 3:45 p.m.
this is not right. when the question says "If the initial and final markers are missing", then it means that the markers are missing in the text, and not that they are empty strings.

Marcin_Rzeszot on Aug. 15, 2019, 12:12 a.m.
nice and clear <3

igharok on Feb. 2, 2020, 8:57 a.m.
Clear and useful for investigating None using in slicing

katharina.noreia on Feb. 27, 2020, 8:43 a.m.
Wow, great solution!

ahin9312 on March 22, 2020, 5:52 a.m.
Nice

ibonyun on April 7, 2020, 7:36 a.m.
You're effectively searching for each marker twice. If the text was very very long and/or you had to do this many many times, it would be more efficient to search just once and store the result in a variable.

yukipr on April 9, 2020, 6:11 a.m.
'else None' is really good,thank you so much!

RezaCoder_4afc97ca9ab94b378542 on April 13, 2020, 5 p.m.
easy to understand thanks

Karing_72cf4aa74db041a4b134d0e on May 18, 2020, 8:02 a.m.
nice solution

kiplimock on May 21, 2020, 12:09 p.m.
Wow! So brief, clear, readable and straightforward. I wrote 16 lines when it's possible to do it in just 4! Thumbs up!

artemis_818 on July 5, 2020, 7:08 a.m.
Sweet and simple

acordado on July 12, 2020, 4:15 p.m.
I forgot None in python, thanks.

n2f on Oct. 15, 2020, 12:44 p.m.
Awesome! neat and clear

Safwan_Samsudeen on Nov. 10, 2020, 5:31 a.m.
Good solution, I did the same thing.

neuro_boy on Dec. 24, 2020, 5:57 p.m.
orgasmic

BlindB on March 29, 2021, 1:01 p.m.
clear

bsquare on Oct. 5, 2021, 7:47 a.m.
Quick and efficient.

juanmsmilla on Oct. 14, 2021, 1:51 p.m.
Clean and clear.

DanielGladkikh on Nov. 2, 2021, 9:30 p.m.
thank yuo for that one)

Pheedan on Dec. 2, 2021, 1:50 p.m.
How is the case solved if end comes before start?

zom100 on Dec. 16, 2021, 11:25 a.m.
+1

zom100 on Dec. 16, 2021, 11:21 a.m.
how will this code deal with text without a begin or end? it is posible in given conditions: *If the initial and final markers are missing then simply return the whole string.

zelaznog on Dec. 17, 2021, 6:32 p.m.
Very good solution, I learn a couple of thing from it.

yanweiqi123 on Feb. 7, 2022, 7:11 a.m.
clear

phongtt2 on May 26, 2022, 1:21 a.m.
ow I didn't know the string find() function returns index of substring. Then I used index() function. Your solution looks so great, nice and neat

olena.rudenko on Sept. 17, 2023, 3:48 p.m.
so much more clear than I did)

StefanPochmann on Feb. 19, 2024, 2:42 a.m.
Nowadays I think I'd prefer shorter lines: ``` def between_markers(text: str, begin: str, end: str) -> str: start = stop = None if begin in text: start = text.find(begin) + len(begin) if end in text: stop = text.find(end) return text[start:stop] ```

walmas on April 17, 2024, 2 a.m.
Wonder what the relative advantage is of .find() vs .index() or if its the same

StefanPochmann on April 17, 2024, 6:51 p.m.
In this case, since I use it only after establishing that the substring is there, the only difference/advantage I'm aware of is that `find` is one letter shorter :-)

Strings Theory

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