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Old 2022-05-02, 15:31   #1
Max0526
 
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Jun 2016
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Default May 2022

https://research.ibm.com/haifa/ponde...s/May2022.html
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Old 2022-05-02, 15:37   #2
Max0526
 
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It seems that the May challenge is too easy.
Python produces the first solution for the regular challenge in under a second, and the the first bonus "*" solution in under 3 minutes on one core.
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Old 2022-05-02, 16:58   #3
uau
 
Jan 2017

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Quote:
Originally Posted by Max0526 View Post
It seems that the May challenge is too easy.
Python produces the first solution for the regular challenge in under a second, and the the first bonus "*" solution in under 3 minutes on one core.
Even that is slower than necessary - there's a straightforward O(n2) algorithm.

By the way, the way to present the problem feels slightly weird to me - the introduction about how every size 2n set contains a size n subset with sum divisible by n doesn't seem to have all that much to do with actual problem. The added constraint removes most of the similarity, as there generally isn't a solution any more for arbitrary lists (consider a list starting with a pair of ones and the rest zeros).
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Old 2022-05-02, 17:12   #4
ryanp
 
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Also feels too simple... my dumb (recursive) Python program is about 15 lines and produces a solution for the first part in a few milliseconds, the second one in 3 seconds.
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Old 2022-05-05, 15:35   #5
Max0526
 
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Quote:
Originally Posted by ryanp View Post
Also feels too simple... my dumb (recursive) Python program is about 15 lines and produces a solution for the first part in a few milliseconds, the second one in 3 seconds.
As a proof of concept, I wrote a long one-line solution in Python.
A 300 loop usually guarantees a solution for both (regular and bonus *) challenges.
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Old 2022-05-06, 19:37   #6
SmartMersenne
 
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Quote:
Originally Posted by Max0526 View Post
As a proof of concept, I wrote a long one-line solution in Python.
A 300 loop usually guarantees a solution for both (regular and bonus *) challenges.
I would love to see that one line after the challenge is over.
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Old 2022-05-11, 14:07   #7
Max0526
 
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Quote:
Originally Posted by SmartMersenne View Post
I would love to see that one line after the challenge is over.
Do you want me to drop it via PM?
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Old 2022-05-11, 14:09   #8
Max0526
 
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The first names are posted, seven of my students among them: https://research.ibm.com/haifa/ponde...s/May2022.html.
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Old 2022-05-12, 06:25   #9
tgan
 
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Quote:
Originally Posted by Max0526 View Post
The first names are posted, seven of my students among them: https://research.ibm.com/haifa/ponde...s/May2022.html.
That is very good sign that you are excellent professor

Last fiddled with by tgan on 2022-05-12 at 06:26
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Old 2022-05-12, 07:03   #10
SmartMersenne
 
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Quote:
Originally Posted by Max0526 View Post
The first names are posted, seven of my students among them: https://research.ibm.com/haifa/ponde...s/May2022.html.
103 solvers!
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