What is the faster way to count substrings in string using python

Question

I'm trying to find a fast algorithm for counting how many times a substring is found in a string using Python. I know there are some builtin functions for doing that but they do no serve my propose. For example, the word "ana" appears 2 times in "banana" but the string method count just returns 1. The code I have so far is:

s = "banana"
sub = "ana"
count = 0
for i in range(4):
    if s.startswith(sub):
        count += 1

If some one knows a better way, please let me know.

danielarend · Answer 1 · 2016-08-02T00:01:01.707

1

possible this:

s = "banana"
sub = "ana"
count = len(s.split(sub))-1

edited Aug 02 '16 at 00:01

answered Aug 01 '16 at 23:43

danielarend

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1

Thank's but it will not work. For example, if instead of "ana" sub has "a" the answer would be incorrect. It would be 4 instead of 3. – user24312 Aug 01 '16 at 23:57
you are right. Edited here – danielarend Aug 02 '16 at 00:00

What is the faster way to count substrings in string using python

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