Straightforward creative solution for Digits Multiplication by nickie - python coding challenges

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Straightforward solution in Creative category for Digits Multiplication by nickie

from operator import mul
from functools import reduce

checkio = lambda n: reduce(mul, (int(d) or 1 for d in str(n)), 1)

Feb. 20, 2014

Comments:

Cjkjvfnby on March 1, 2014, 8:21 p.m.
You can omit last argument of reduce. Pydocs: If the optional initializer is present, it is placed before the items of the iterable in the calculation.

mikwaheeri on May 8, 2014, 4:25 p.m.
This is a nice solution, but I'm having trouble figuring out how you handle the value of 0. Can you please explain how you handle 0? Also, can you explain the (int(d) or 1 for d in str(n)) part? I'm not sure when the 1 gets used instead of int(d). I'm thinking the two are related, but I've yet to be able to figure it out. Thanks

nickie on May 8, 2014, 7 p.m.
In Python, "a or b" evaluates to "a" unless this produces a false value (i.e., False, 0, None, an empty list, etc.), in which case it evaluates to "b". Therefore, with "int(d) or 1", if the value of a digit "int(d)" is zero, then "1" is used instead. This effectively discards the zeroes without affecting the rest of the product.

mikwaheeri on May 8, 2014, 7:01 p.m.
Thank you!!

Columpio on May 26, 2014, 4:44 p.m.
The same as mine! ^_^ It's so beautiful, when people know standart library!

nennogabriel on Aug. 5, 2014, 4:03 p.m.
nice, but I like my golf solution

Arandomusername on Feb. 26, 2015, 1:51 p.m.
I have a similiar implementations but without the import statements (It's possible)

nickie on Feb. 26, 2015, 9:34 p.m.
Only <a href="http://www.checkio.org/mission/digits-multiplication/publications/Arandomusername/python-27/finally-a-good-use-for-reduce/">your solution</a> is for Python 2. Unfortunately, in Python 3, `reduce` was moved to `functools`. Obviously `mul` can be replaced with a lambda.

Arandomusername on Feb. 27, 2015, 12:09 p.m.
That's true, I used python 2 because import statements steal a huge amount of performance (tested with timeit)

Nocturne13 on June 14, 2023, 11:24 a.m.
Very nice solution, using combination of two very popular python libraries. Also it's a very smart solution for excluding zeroes from multiplication, using or keyword.

Strings and Integers

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