Search found 56 matches

by RobertStanforth
Sat Feb 15, 2020 4:37 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 023
Replies: 56
Views: 18268

Re: Problem 023

Hello guys, I started to solve Project Euler problems recently, I wrote below code to prevent adding duplicate items to collection but it returns incorrect answer at the end. I have merged your post with the existing topic for Problem 23. Please do not post code (or other aids to solving) in this f...
by RobertStanforth
Wed Feb 12, 2020 8:03 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 610
Replies: 18
Views: 5128

Re: Problem 610

The question states The rules do not place any restriction on the number of occurrences of M, so all integers have a valid representation. but doesn't explain how to get negative integers, and I got the tick with an answer which assumes that negative integers don't have a valid representation. I th...
by RobertStanforth
Tue Jan 21, 2020 9:24 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 597
Replies: 3
Views: 343

Re: Problem 597

aTree wrote:
Tue Jan 21, 2020 7:00 am
Is this log base 10 or base e?
You can take it to be base $e$ ... but actually it doesn't matter because a different base would just scale all speeds by the same constant without affecting the sequence of events.
by RobertStanforth
Sat Jan 04, 2020 9:04 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 684
Replies: 4
Views: 1140

Re: Problem 684

Do you have to find the smallest digit sum for each term of the fibonacci sequence from the 2nd to the 90th? No, that is not correct. $S(n)$ is not digitsum. Instead, $s(n)$ is the inverse digit sum, so $\mathrm{digitsum}(s(n)) = n$. Note also that $S$ is the sum of $s$. So, (given a Fibonacci numb...
by RobertStanforth
Mon Nov 18, 2019 7:04 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 688
Replies: 7
Views: 906

Re: Problem 688

vamsikal3 wrote:
Mon Nov 18, 2019 6:07 am
The problem text reads: It is impossible to divide 10 into 5 non-empty piles and hence f(10,5)=0.
Thank you for pointing this out. The wording has now been amended.
by RobertStanforth
Mon Nov 18, 2019 7:40 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 689
Replies: 3
Views: 717

Re: Problem 689

Your values of $f$ are correct (albeit with the interpretation of the $\pi^2/6$ value as a limiting case, because $f(x)$ is only defined if $x$ is strictly less than 1).

For answer format, the leading zero is required, as in 0.abcdefgh
by RobertStanforth
Fri Oct 18, 2019 4:34 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 679
Replies: 2
Views: 703

Re: Problem 679

LangerJan wrote:
Fri Oct 18, 2019 9:43 am
Problem 679 (View Problem)

Quick question about counting keywords: Does "AREAREA" count as two occurrences of "AREA"?
Yes, it counts as two occurrences.
by RobertStanforth
Thu Oct 03, 2019 6:25 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 570
Replies: 1
Views: 491

Re: Problem 570

voltara wrote:
Thu Oct 03, 2019 1:03 am
The problem description for 570 contains a broken image; the filename is misspelled "p570-slowflakes.png" instead of "p570-snowflakes.png".
Thank you for letting us know. The broken image has now been fixed.
by RobertStanforth
Mon Sep 23, 2019 5:31 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 669
Replies: 5
Views: 3761

Re: Problem 669

At this point, I'm about 1 step away from challenging the answer to this problem. I know a fair number of people have already solved this problem. I know I have everything in correctly, the program appears to operate just fine. I've done just about everything I can. Next step is to verify each step...
by RobertStanforth
Wed Aug 14, 2019 6:02 pm
Forum: News, Suggestions, and FAQ
Topic: Bookmark / Pinning a problem?
Replies: 26
Views: 4733

Re: Bookmark / Pinning a problem?

To answer your original question, the Project Euler site does not currently have any specific functionality for bookmarking problems (except for "filter by solved/unsolved"). The work-around I suggested earlier of using browser bookmarks may still be viable for the cross-device use case that you des...
by RobertStanforth
Sun Aug 11, 2019 5:49 pm
Forum: News, Suggestions, and FAQ
Topic: Bookmark / Pinning a problem?
Replies: 26
Views: 4733

Re: Bookmark / Pinning a problem?

Your web browser's bookmarking facility should be adequate for this job.
by RobertStanforth
Mon Jul 29, 2019 6:54 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 122
Replies: 14
Views: 5798

Re: Problem 122

RishadanPort wrote:
Sun Jul 28, 2019 5:31 pm
Is m(1) considered 0 or 1?

I'm assuming 0 becomes you don't need any multiplication
Yes, your reasoning is correct.
by RobertStanforth
Mon Jul 29, 2019 6:43 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 19
Views: 9217

Re: Problem 351

RishadanPort wrote:
Mon Jul 29, 2019 6:34 am
ok I solved this problem...

I am really wondering tho, why H(1000), H(1 000 000), and H(100 000 000) all look so similar... Can anyone explain? feel free to send me private message.
This question would be better asked in the solutions thread for this problem on the main site.
by RobertStanforth
Tue Jul 16, 2019 6:30 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 19
Views: 9217

Re: Problem 351 Visibility of extremely far away orchard

Let the middle orchard represent (0, 0). if I have say an orchard that is on the X-Axis shifted (100 000 000 - 1) away but shifted up or below by 1, -- do I assume I can see this orchard even tho the line is extremely close to just horizontal line? I am guessing all orchards are points with no widt...
by RobertStanforth
Thu May 09, 2019 9:06 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 653
Replies: 2
Views: 2908

Re: Problem 653

My problem that I've realised that if two particles were to move toward each other while they are an odd number of millimetres away, they would meet at a point with half-integer position ( with a .5); which seemingly goes against what the rest of the problem is implying i.e that all values are inte...
by RobertStanforth
Mon Apr 22, 2019 7:09 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 013
Replies: 76
Views: 23662

Re: Problem 13

reza1615 wrote:
Mon Apr 22, 2019 4:40 am
Hi all,
I don't undrestand the description of problem 13. what does it need? would you please tell me by an example?
Hi reza1615,
I merged your post with the existing topic for this problem. You may find what you need in this thread.
by RobertStanforth
Tue Feb 19, 2019 8:48 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 656
Replies: 9
Views: 1873

Re: Problem 656

vamsikal3 wrote:
Tue Feb 19, 2019 4:17 am
Can I PM someone to verify my result for the 21st term in the sequence given in the example for square_root(31)?
No, that is still not the purpose of this forum.
As Animus said, "it is not appropiate to ask for help for recent problems that have not even reached 100 solvers".
by RobertStanforth
Fri Feb 01, 2019 6:27 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 090
Replies: 46
Views: 14297

Re: Problem 090

For the purposes of this problem, an "arrangement of two cubes" means a set of two cubes, where each cube is a set of six digits. Thus your "set of sets" interpretation is correct. If two "arrangements of two cubes" are found to differ from one another only be reordering the cubes, or by reordering ...
by RobertStanforth
Sun Nov 18, 2018 11:46 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 643
Replies: 8
Views: 3520

Re: Problem 643

vamsikal3 wrote:
Sun Nov 18, 2018 9:35 am
The correct text is: For example, 24 and 40 are 2-friendly because ....
Thanks, Vamsi. This is fixed now.
by RobertStanforth
Fri Nov 16, 2018 10:02 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 420
Replies: 11
Views: 5265

Re: Problem 420

To be clear: 'squaring' a matrix refers specifically to matrix multiplication of a matrix with itself.