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How do I get the position of a string inside a list in Python?

I am trying to get the position of a string inside a list in Python? How should I do it?

For example, when a user provides a sentence "Hello my name is Dolfinwu", I turn the entire sentence into a list beforehand, and I want to get the positions of each "o" right here, how can I do it? In this case, the position of the first "o" is "4", and the position of the second "o" is "18". But obviously, users would enter different sentences by using different words, so how can I get a specific string value's position under this unpredictable situation?

I have tried this code as below. I know it contains syntax errors, but I could not figure out something better.


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  1. sentence = list(input('Please type a sentence: '))
  2. space = ' '
  3.  
  4. for space in sentence:
  5.     if space in sentence:
  6.         space_position = sentence[space]
  7.         print(space_position)
4 Weeks Ago #1
2 3704
Banfa
9,052 Expert Mod 8TB
a. Don't convert the string to a list, that isn't helpful
b. Use either the find or index method on the string depending on how you wish to handle errors (https://docs.python.org/2/library/string.html)
c. Consider using raw_input instead of input so that you always have a string.
3 Weeks Ago #2
SioSio
246 128KB
When searching for a character string using the "find" method or "index" method, there may be multiple search character strings, so it is necessary to search while shifting the start position in a loop.
In such cases, the "finditer" method is useful.
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  1. import re
  2. sentence = str(input("Please type a sentence:"))
  3. r = re.finditer("o",sentence)
  4. for e in r:
  5.     print (e.start())
3 Weeks Ago #3

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