#elements of seq A in seq B

Jan Kaliszewski zuo at chopin.edu.pl
Fri Aug 21 01:44:43 CEST 2009


20-08-2009 o 13:01:29 Neal Becker <ndbecker2 at gmail.com> wrote:

> I meant #occurrences of characters from the set A in string B

But:

1) separately for each element of A? (see Simon's sollution with
defaultdict)

2) or total number of all occurrences of elements of A? (see below)


20-08-2009 o 14:05:12 Peter Otten <__peter__ at web.de> wrote:

> identity = "".join(map(chr, range(256)))
> n = len(b) - len(b.translate(identity, a))

Nice, though I'd prefer Simon's sollution:

     a = set(a)
     n = sum(item in a for item in b)

Regards,
*j

-- 
Jan Kaliszewski (zuo) <zuo at chopin.edu.pl>



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