When Is Cheryl's Birthday?

#1

Post by jonp » Sat, Apr 25, 2015, 12:17 AM UTC

When Is Cheryl's Birthday?
nbviewer.ipython.org

Re: When Is Cheryl's Birthday?

#2

Post by ghurtado » Sat, Apr 25, 2015, 2:46 AM UTC

I thought this was a great puzzle when I first saw it. IMHO, it is more satisfying to "think through it" without paper and pencil, since it is relatively simple to resolve.

The Python solution proposed is really great, in that it captures both the expressive and functional spirit of the language.

Re: When Is Cheryl's Birthday?

#3

Post by picardo » Sat, Apr 25, 2015, 2:59 AM UTC

I'd be interested in seeing a solution in Prolog.

Re: When Is Cheryl's Birthday?

#4

Post by ternaryoperator » Sat, Apr 25, 2015, 3:03 AM UTC

ghurtado wrote: post #2

I thought this was a great puzzle when I first saw it. IMHO, it is more satisfying to "think through it" without paper and pencil, since it is relatively simple to resolve. The Python solution proposed is really great, in that it captures both the expressive and functional spirit of the language.

>since it is relatively simple to solve

You are overestimating how simple it is.There are more than 1200 comments on the solution on the NYTimes[1] almost all of them arguing that other dates are correct.

[1] http://www.nytimes.com/2015/04/15/science/answer-to-the-sing...

Re: When Is Cheryl's Birthday?

#5

Post by [deleted] » Sat, Apr 25, 2015, 3:08 AM UTC

[deleted]

Re: When Is Cheryl's Birthday?

#6

Post by sigterm » Sat, Apr 25, 2015, 3:18 AM UTC

picardo wrote: post #3

I'd be interested in seeing a solution in Prolog.

it was posted here before:

https://news.ycombinator.com/item?id=9395604

Re: When Is Cheryl's Birthday?

#7

Post by mattbeckman » Sat, Apr 25, 2015, 3:27 AM UTC

Friend of mine wrote a Scala solution: http://www.agileatwork.com/scala-solution-to-cheryls-birthda...

Re: When Is Cheryl's Birthday?

#8

Post by [deleted] » Sat, Apr 25, 2015, 3:29 AM UTC

[deleted]

Re: When Is Cheryl's Birthday?

#9

Post by Jach » Sat, Apr 25, 2015, 3:32 AM UTC

ternaryoperator wrote: post #4

ghurtado wrote: post #2

I thought this was a great puzzle when I first saw it. IMHO, it is more satisfying to "think through it" without paper and pencil, since it is relatively simple to resolve. The Python solution proposed is really great, in that it captures both the expressive and functional spirit of the language.

>since it is relatively simple to solve You are overestimating how simple it is.There are more than 1200 comments on the solution on the NYTimes[1] almost all of them arguing that other dates are correct. [1] http://www.nytimes.com/2015/04/15/science/answer-to-the-sing...

It's relatively simple, if you're the kind of person who grasps that 1+1*0 is not 0 under most parsers and under the order of operations implied by e.g. the vector space axioms...

Re: When Is Cheryl's Birthday?

#10

Post by haddr » Sat, Apr 25, 2015, 3:53 AM UTC

still looking for solution using RDF/OWL logical reasoning...

the python solution is neat, but i have a feeling that there are tools that are more native to these kind of problems than general purpose programming language.