Search found 528 matches

by jaap
Sat Mar 16, 2019 8:59 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 600
Replies: 1
Views: 103

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.
by jaap
Wed Mar 06, 2019 4:21 pm
Forum: News, Suggestions, and FAQ
Topic: Project Euler Style Sheet Update
Replies: 33
Views: 1354

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...
by jaap
Mon Mar 04, 2019 9:30 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 425
Replies: 28
Views: 5548

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
by jaap
Wed Feb 20, 2019 10:57 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 656
Replies: 9
Views: 517

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.
by jaap
Sat Jan 12, 2019 10:00 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 196
Replies: 34
Views: 8940

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.
by jaap
Mon Dec 24, 2018 5:49 am
Forum: News, Suggestions, and FAQ
Topic: Hairsplitting Curiosity (w/ Alliteration)...
Replies: 6
Views: 1173

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...
by jaap
Sat Dec 15, 2018 5:48 am
Forum: Discrete Mathematics
Topic: Sorting...
Replies: 4
Views: 1622

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.
by jaap
Fri Nov 16, 2018 3:47 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 13
Views: 6748

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.
by jaap
Fri Nov 16, 2018 2:09 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 13
Views: 6748

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...
by jaap
Fri Nov 16, 2018 1:33 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 640
Replies: 7
Views: 2156

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.
Sure, go ahead.
by jaap
Fri Nov 16, 2018 10:31 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 351
Replies: 13
Views: 6748

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...
by jaap
Thu Nov 08, 2018 10:30 am
Forum: Clarifications on Project Euler Problems
Topic: Problem 640
Replies: 7
Views: 2156

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.
by jaap
Wed Oct 17, 2018 8:46 am
Forum: Number
Topic: "Fixed Points"
Replies: 5
Views: 2905

Re: "Fixed Points"

Oh, it's the unmistakable work of Raymond Smullyan. The strings we are working with are expressions. Just like an ordinary arithmetical expression like "4+5" can be evaluated to yield "9", these strings have their own type of arithmetic that can be used to evaluate them and yield another string. You...
by jaap
Tue Oct 16, 2018 6:30 am
Forum: Number
Topic: "Fixed Points"
Replies: 5
Views: 2905

Re: "Fixed Points"

kenbrooker wrote:
Mon Oct 15, 2018 9:47 pm
In this case, X is a string and X is a function, a function of itself.
In what case? In what context do you have strings that are also functions?

It is hard to tell what misunderstandings you might have if you don't show the original text that you might be misunderstanding.
by jaap
Tue Oct 02, 2018 12:36 pm
Forum: Resources
Topic: Please Help re UVa @ https://uva.onlinejudge.org
Replies: 7
Views: 2325

Re: Please Help re UVa @ https://uva.onlinejudge.org

Main.java:2: error: class aUVa100 is public, should be declared in a file named aUVa100.java It IS "declared in a file named aUVa100.java" but... I don't know the online IDE/compiler this site uses, and I don't think I can access it without becoming a member. It clearly thinks it is in a file calle...
by jaap
Mon Oct 01, 2018 7:57 am
Forum: Resources
Topic: Please Help re UVa @ https://uva.onlinejudge.org
Replies: 7
Views: 2325

Re: Please Help re UVa @ https://uva.onlinejudge.org

Maybe you need to make the class public for it to run:

Code: Select all

public class aUVa100
by jaap
Tue Sep 25, 2018 6:14 pm
Forum: News, Suggestions, and FAQ
Topic: Progress Page turned orange.
Replies: 1
Views: 1583

Re: Progress Page turned orange.

See euler's post here:
viewtopic.php?f=5&t=6663#p52409
by jaap
Fri Sep 07, 2018 12:03 pm
Forum: Clarifications on Project Euler Problems
Topic: Problem 012
Replies: 99
Views: 23097

Re: Problem 012

sriramrajan wrote:
Fri Sep 07, 2018 9:04 am
My answer has 112 divisors / factors and is the first one in the series but was declared wrong.
The question is not asking for the first one with 112 divisors, but for
... the first triangle number to have over five hundred divisors?
by jaap
Sat Jul 28, 2018 11:42 am
Forum: News, Suggestions, and FAQ
Topic: Mark problems that can be figured out through math alone
Replies: 3
Views: 1228

Re: Mark problems that can be figured out through math alone

There is a thread on this forum discussing which problems can be solved with paper and pencil:
viewtopic.php?f=12&t=1982