CodingBat: Python | Hacker News Reader

CodingBat: Python

codingbat.com

24 pointsshawndumas7 comments

Instead of

    def sum_double(a, b):
        # Store the sum in a local variable
        sum = a + b
        # Double it if a and b are the same
        if a == b:
            sum = sum * 2
        return sum

I wrote:

    def sum_double(a, b):
        return (a+b)*2 if a==b else a+b

My solution was accepted. Apparently the site evaluates the python program. This is much better than some online C++ test I once took, where my entry had to match perfectly a pre-canned solution letter by letter (it would even balk on differences in whitespace).

Awesome! Back when I worked at a bank we used to do timed challenges over at http://javabat.com (same thing but for java). Now that I hack Python all day this is much more my thing, although it's not that much of a challenge, it'll give me somewhere to send the greenhorns.

codingbat is javabat renamed. Presumably because they added python

The idea is neat, but all of these problems are trivial (that is, they’re about following a simple set of very concrete instructions rather than figuring anything out). It would be a more interesting site if there were some more challenging problems.

The real idea here is mentioned in the about page: http://codingbat.com/about.htm

Summarised... a CS lecturer noticed that students who struggle with the small things like syntax, have less time to focus on the big issues of algorithms and data structures. The site gives short practice problems to that effect.

More challenging problems would be interesting, but there's a limit to what you can fit in the stated goal of short problems. Although, I wouldn't say that more difficult problems could be solved in similar space :)

Okay, I agree that “you also need skill in the ‘small’ – 10 or 20 line methods”, but almost all of these can be implemented in 1 or 2 lines.

Nick Parlante has done good with this project. At UCSB, I'm on a team that's doing research into running this kind of website with unit tests, etc. for even more languages and for harder problems, as a curriculum aid.

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