Saturday, 15 May 2010

python: Finding a substring within a string -



python: Finding a substring within a string -

i'm trying write programme counts how many times substring appears within string.

word = "wejmfoiwstreetstreetskkjoih" streets = "streets" count = 0 if streets in word: count += 1 print(count)

as can see "streets" appears twice lastly s of streets origin of streets. can't think of way loop this.

thanks!

can done using regex

>>> import re >>> text = 'streetstreets' >>> len(re.findall('(?=streets)', text)) 2

from the docs:

(?=...)

matches if ... matches next, doesn’t consume of string. called lookahead assertion. example, isaac (?=asimov) match 'isaac ' if it’s followed 'asimov'.

python

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