## Search found 535 matches

Fri Jun 28, 2019 7:39 am
Forum: News, Suggestions, and FAQ
Topic: Errors/Warnings/Bugs
Replies: 497
Views: 94349

### Re: Errors/Warnings/Bugs

We cannot make two consecutive posts in the same solution forum. I think you should be able to edit your post and add the content in the same post. I think you misunderstood the problem. The post is not shown in the problem thread so it cannot be edited. Hopefully it is just a caching problem that ...
Thu Jun 27, 2019 9:03 am
Forum: Discrete Mathematics
Topic: The Satisfiability Problem... NP or P?!
Replies: 4
Views: 1507

### Re: The Satisfiability Problem... NP or P?!

https://medium.com/swlh/the-boolean-satisfiability-problem-solved-48ceb5550115 It is badly explained, and is certainly not a proof. It ends with: Considering that it is able to find a solution in most indices, as it usually works with a high probability (80%) then you can always try another index t...
Tue May 28, 2019 12:44 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 672
Replies: 2
Views: 3676

### Re: Problem 672

Thanks for fixing that hk. Shouldn't there be a floor function around the $\frac{7^K-1}{11}$ term? I don't think there is a universally accepted meaning for a sum where the upper limit for the index variable is not an integer. Please investigate if $\frac{7^K-1}{11}$ isn't an integer for the values ...
Tue May 28, 2019 11:35 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 672
Replies: 2
Views: 3676

### Problem 672

Is "no nothing" a typo for "do nothing"?

Shouldn't there be a floor function around the $\frac{7^K-1}{11}$ term? I don't think there is a universally accepted meaning for a sum where the upper limit for the index variable is not an integer.
Mon May 27, 2019 12:40 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 671
Replies: 3
Views: 2928

### Re: Problem 671

I have not solved this question yet, but have worked out F_4(3) on paper. @amagri: I believe those are indeed forbidden, so for both those reasons you cannot use a 1x3 tile when n=3. @MuthuVeerappanR: I think rotations around the axis of the loop are not considered different. I get 24+24+24+24+8 = 1...
Mon May 20, 2019 12:31 am
Forum: News, Suggestions, and FAQ
Topic: Recover account
Replies: 4
Views: 2650

### Re: Recover account

hk wrote:
Sun May 19, 2019 11:55 am
Last Visit:

Saturday, 19th May 2018, 11:11 pm

It is 2019 now, you know.
Fri May 17, 2019 5:36 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 647
Replies: 2
Views: 2717

### Re: Problem 647

I know that quite some folk have solved this one already and it doesn't look too daunting, really - except that: well I'm getting 186 and not 184 as result for F_3(100). It really is 184. If you want, you can send me the pairs (A,B) that make up the sum by private message (you should have only four...
Sat Mar 16, 2019 8:59 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 600
Replies: 1
Views: 446

### Re: Problem 600

RichardDL wrote:
Sat Mar 16, 2019 4:13 pm
18, 5, 1, 4, 3, 3, 2
18, 5, 2, 3, 3, 4, 1
Hexagons that are mirror images of one another are congruent.
Wed Mar 06, 2019 4:21 pm
Forum: News, Suggestions, and FAQ
Topic: Project Euler Style Sheet Update
Replies: 33
Views: 7452

### Re: Project Euler Style Sheet Update

First, I don't know how to switch from the dark theme to light or vice versa. Is this missing, hidden, or am I just blind? In the Account tab, there is a section with Country, Language etc, including Theme. Change the Theme from Dark to Default (and click the Update Details button) to go back to wh...
Mon Mar 04, 2019 9:30 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 425
Replies: 28
Views: 6279

### Re: Problem 425

pxor wrote:
Mon Mar 04, 2019 4:03 am
Hey, could anyone explain how is 503 connected to 2?
503 is connected to 103, and the rest is via the chain given as an example in the problem:
2 ↔ 3 ↔ 13 ↔ 113 ↔ 103 ↔ 503
Wed Feb 20, 2019 10:57 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 656
Replies: 9
Views: 1105

### Re: Problem 656

In the wording of the problem, I don't think it is a good idea to use the letter n for two different variables - first as the index of the sequence, then as an element of T. I think it would be better to change the second use to a variable named t for example.
Mon Jan 28, 2019 10:31 am
Forum: News, Suggestions, and FAQ
Topic: désaccord sur décimales de sqrt(2)
Replies: 1
Views: 2450

### Re: désaccord sur décimales de sqrt(2)

Sat Jan 12, 2019 10:00 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 196
Replies: 34
Views: 9757

### Re: Problem 196

tchiari wrote:
Sat Jan 12, 2019 6:53 pm
I'm wondering if someone would be willing to give me a prime that is part of a triple but not on my list. That would help me to figure out if the issue is with how I'm generating/determining my primes or with how I'm looking for triples.
I've sent a private message.
Mon Dec 24, 2018 5:49 am
Forum: News, Suggestions, and FAQ
Topic: Hairsplitting Curiosity (w/ Alliteration)...
Replies: 6
Views: 1650

### Re: Hairsplitting Curiosity (w/ Alliteration)...

https://projecteuler.net/about=aliases If you hover over a poster's name in a solution thread (specifically the ones that are in italics, which indicates it is an alias), you will see a tooltip showing the account username. Unfortunately the quoting system always seems to display the username, not i...
Sat Dec 15, 2018 5:48 am
Forum: Discrete Mathematics
Topic: Sorting...
Replies: 4
Views: 5156

### Re: Sorting...

You have re-invented the Pigeonhole sort.

The wiki page on sorting algorithms has a separate section for non-comparison integer sorts like this. Its main disadvantage is that its running time and its memory requirements depend on max, not just on n.
Fri Nov 16, 2018 3:47 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 15
Views: 7834

### Re: Problem 351

If you ever need more than, say, 600MB of data, then you are probably doing it wrong. You are either using the wrong solving method, or maybe you just don't need to have all of that data in memory at the same time.
Fri Nov 16, 2018 2:09 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 15
Views: 7834

### Re: Problem 351

Cheers Jaap, I'm afraid I'll have to confess my ignorance on the first question (I'll google that though). I do use vectors, yes, but I would have thought it would pose problems of efficiency too as it will take up a lot of memory. I'll try that approach over the weekend though and see what happens...
Fri Nov 16, 2018 1:33 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 640
Replies: 7
Views: 2701

### Re: Problem 640

LarryBlake wrote:
Fri Nov 16, 2018 12:55 pm
@jaap, may I PM you my assumptions and a question? I believe I'm having the same difficulty tuple describes.
Fri Nov 16, 2018 10:31 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 15
Views: 7834

### Re: Problem 351

On my system and using C/C++, defining an array this size immediately causes a 'Segmentation fault' - and the number spaces required only get larger on some of the more difficult problems on PE. Am I missing something? Do you know the difference between the stack and heap memory? Do you know how to...
Thu Nov 08, 2018 10:30 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 640
Replies: 7
Views: 2701

### Re: Problem 640

It seems I'm having the same problem as tuple, as I get those answers too.

Edit: Solved it now. I had made an assumption that was not true in every situation, and from reading the problem's thread, many others did so too.