Since the problems are made publicly available under Creative Commons License, once the problem is out, and I solve the problem whichever way, how can Project Euler require me to not share my solution online? (PE can request us to not post solutions online, but requiring me to not post my solutions online is not any of PE's business) Last time I checked, the solution is mine and I am within limits free to do whatever I want with the solution I came up with ... If Project Euler locks my account, I will simply use https://projecteuler.info to check my solutions and continue to make my solutions available online.

Thoughts?

## Can Project Euler require users to not post their solutions online?

### Re: Can Project Euler require users to not post their solutions online?

The thing is simple:

Project Euler considers itself a community. Members having a public, unlisted or permanently delisted account are requested not to place solutions online outside PE.

If they do place solutions online outside PE they place themselves outside the community, their account is locked and they don't exist anymore as far a we are concerned. We don't spend any time or other resources on people outside our community.

(The reason why we don't delete their accounts is to make it impossible to start over again with an account with the same ID).

Project Euler considers itself a community. Members having a public, unlisted or permanently delisted account are requested not to place solutions online outside PE.

If they do place solutions online outside PE they place themselves outside the community, their account is locked and they don't exist anymore as far a we are concerned. We don't spend any time or other resources on people outside our community.

(The reason why we don't delete their accounts is to make it impossible to start over again with an account with the same ID).

- euler
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### Re: Can Project Euler require users to not post their solutions online?

@openBook: I'm a little confused by what you're asking here.

Project Euler is a community of people who share a passion for solving programming/mathematical problems. A team of dedicated and talented members work incredibly hard to produce high quality problems on a regular basis. There are no costs involved in being part of this amazing community. A reasonable request is made that no one ruins for others the opportunity to learn and the rewarding experience of discovery achieved by solving these problems. And yet you ask what is wrong with deliberately choosing to undermine the efforts and wishes of the team?

Project Euler is a community of people who share a passion for solving programming/mathematical problems. A team of dedicated and talented members work incredibly hard to produce high quality problems on a regular basis. There are no costs involved in being part of this amazing community. A reasonable request is made that no one ruins for others the opportunity to learn and the rewarding experience of discovery achieved by solving these problems. And yet you ask what is wrong with deliberately choosing to undermine the efforts and wishes of the team?

*impudens simia et macrologus profundus fabulae*

### Re: Can Project Euler require users to not post their solutions online?

@Colin:

Please read a previous post by openbook. https://projecteuler.chat/viewtopic.php?p=59324#p59324

Please read a previous post by openbook. https://projecteuler.chat/viewtopic.php?p=59324#p59324

### Re: Can Project Euler require users to not post their solutions online?

@hk:

Based on your interpretation of what it means to be a member of the Project Euler community, I am definitely not a member of the Project Euler community.

@euler:

quoting euler:

Are you sure that this is the case?

Here is an example from personal experience, back when I was solving problems as 'vamsikal3', I was 100% a member of the Project Euler community based on hk's interpretation. Then, I ran into PE 152. Based on my mathematical background at that time, I ran into a wall, with my then mathematical knowledge, I could not solve PE 152. Frustrated, I started searching the web for "Project Euler Problem 152" and ran into a Haskell wiki that had solutions to quite a few PE problems in the 1 - 200 range. The PE team at that time tried to shut that wiki down. Anyways, I saw the code to solve the problem, I could not make head-or-tail of the densely written Haskell code. So, I simply ran the code and got the answer. Then, I entered the answer and got the green check mark! Then, I started reading the forum threads, and guess what, I could not understand the posts as I did not have the mathematical background. After a year or more, I went back to the PE 152 thread hoping there was a post I could understand and guess what:

After having successfully understood and implemented an algorithm to solve PE 152, I could say one thing: No way, with my mathematics background at that time, could I have pieced together the solution to PE 152. So, not everyone can invent the wheel, but when someone has invented the wheel, someone like me could possibly invent the wheel-barrow!

I could have waited forever and could never have had the "Aha" experience with PE 152. So, whoever allowed me to unlock PE 152, together with a nice post by

I rest my case ...

Based on your interpretation of what it means to be a member of the Project Euler community, I am definitely not a member of the Project Euler community.

@euler:

quoting euler:

**A reasonable request is made that no one ruins for others the opportunity to learn and the rewarding experience of discovery achieved by solving these problems.**

Are you sure that this is the case?

Here is an example from personal experience, back when I was solving problems as 'vamsikal3', I was 100% a member of the Project Euler community based on hk's interpretation. Then, I ran into PE 152. Based on my mathematical background at that time, I ran into a wall, with my then mathematical knowledge, I could not solve PE 152. Frustrated, I started searching the web for "Project Euler Problem 152" and ran into a Haskell wiki that had solutions to quite a few PE problems in the 1 - 200 range. The PE team at that time tried to shut that wiki down. Anyways, I saw the code to solve the problem, I could not make head-or-tail of the densely written Haskell code. So, I simply ran the code and got the answer. Then, I entered the answer and got the green check mark! Then, I started reading the forum threads, and guess what, I could not understand the posts as I did not have the mathematical background. After a year or more, I went back to the PE 152 thread hoping there was a post I could understand and guess what:

**vvenkai**wrote a very nice post on how to solve PE 152 (in 250 ms). I read that post and then without looking at his source code which was in Java, I re-implemented his/her algorithm in Kotlin. I used big integers to avoid worrying about overflow, so my code ran in about 6 seconds.After having successfully understood and implemented an algorithm to solve PE 152, I could say one thing: No way, with my mathematics background at that time, could I have pieced together the solution to PE 152. So, not everyone can invent the wheel, but when someone has invented the wheel, someone like me could possibly invent the wheel-barrow!

I could have waited forever and could never have had the "Aha" experience with PE 152. So, whoever allowed me to unlock PE 152, together with a nice post by

**vvenkai**allowed me to get a feel for what mathematics I do not know and what kind of mathematical techniques I should try to learn.I rest my case ...

- euler
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### Re: Can Project Euler require users to not post their solutions online?

You seem to have completely ignored my question. Do you believe you have earned the right to define the "rules" according to your own standards?

If you feel strongly about these matters, then I urge you to begin contributing. After you've made significant contributions and have become part of the team, then you could get involved in those discussions. Initially you would see the commitment and hard work that goes into problem development. This might help you develop a sense of how upsetting it is to see problems ruined. But ultimately it would also give you insights into how much and how often we continue to re-evaluate what we do. We are under no illusions that everything we do is perfect, and we continue to listen to suggestions from members of the community, but with all things considered the team have a shared consensus that we are doing the best we can.

It seems to me you are saying emphatically: "I have no idea what is going on behind the scenes. I don't really care. I just want to do things my way."

What members do privately is up to them, but when those actions have a public consequence, that is a different matter.

If you feel strongly about these matters, then I urge you to begin contributing. After you've made significant contributions and have become part of the team, then you could get involved in those discussions. Initially you would see the commitment and hard work that goes into problem development. This might help you develop a sense of how upsetting it is to see problems ruined. But ultimately it would also give you insights into how much and how often we continue to re-evaluate what we do. We are under no illusions that everything we do is perfect, and we continue to listen to suggestions from members of the community, but with all things considered the team have a shared consensus that we are doing the best we can.

It seems to me you are saying emphatically: "I have no idea what is going on behind the scenes. I don't really care. I just want to do things my way."

What members do privately is up to them, but when those actions have a public consequence, that is a different matter.

*impudens simia et macrologus profundus fabulae*

### Re: Can Project Euler require users to not post their solutions online?

Right, you're not any more.

Good riddance.

@Colin:

openBook is an outsider and no member any more. Once he was but he has placed himself out of our community. If you look up his account you will see it's locked.

### Re: Can Project Euler require users to not post their solutions online?

There's no requirement to solve the problems in order.openBook wrote: ↑Thu Jan 28, 2021 2:36 pm Are you sure that this is the case?

Here is an example from personal experience, back when I was solving problems as 'vamsikal3', I was 100% a member of the Project Euler community based on hk's interpretation. Then, I ran into PE 152. Based on my mathematical background at that time, I ran into a wall, with my then mathematical knowledge, I could not solve PE 152.

Here's another example from personal experience: I started solving Project Euler problems no later than 2008, because my forum account dates from that year. I have currently solved 519 problems. But there are four problems from the first 200 that I still haven't solved; there are various problems where I think my solution ought to work but it doesn't; others where I have an idea about the approach but haven't yet put in the legwork (in particular, I need to finish studying Diophantine quadratics); and others where I have no clue how to even start.

Other problems which I once had no clue how to tackle with execution times of less than millennia have fallen to techniques which I learnt from the discussion threads of problems I did solve, allowing me to work up a chain of increasing difficulty. I spent a month last year really getting to grips with Dirichlet convolution and writing optimised library functions to handle various variants on the theme. There's plenty of valuable learning material on PE itself once you unlock it, albeit not structured or indexed.

### Re: Can Project Euler require users to not post their solutions online?

@euler:

quoting euler:

I have worked with the Problem Development Team and contributed to 5 PE problems. I do have some sense of how much effort goes into coming up with the problems. I even had my own hangar for some amount of time. All the problems I came up with were when I was working through a number theory textbook.

Do you really think, that someone posting a solution to a PE problem online has ruined the problem?

Think of PE as a university course in mathematics. The analogy being, the more effort you put into a course, the more you get out of it. Now, people with different abilities take the course. Some are A+ category students and they require no help from anyone in acing the course. Even if you give these A+ students the solutions they won't take a look at them. Then, there are some students who are happy to get a B for various reasons ((a) do not have the intellectual firepower, (b) not enough time due to other responsibilities etc.) So, if someone is willing to help out these B category students or if enough of these B category students try to pool their resources and solve the problems, is that wrong? To paraphrase from the website: PE is for education and entertainment.

How are you educating people by denying them access to some material which might help them understand what is it that they need to learn to become better at solving PE problems?

quoting euler:

**This might help you develop a sense of how upsetting it is to see problems ruined.**I have worked with the Problem Development Team and contributed to 5 PE problems. I do have some sense of how much effort goes into coming up with the problems. I even had my own hangar for some amount of time. All the problems I came up with were when I was working through a number theory textbook.

Do you really think, that someone posting a solution to a PE problem online has ruined the problem?

Think of PE as a university course in mathematics. The analogy being, the more effort you put into a course, the more you get out of it. Now, people with different abilities take the course. Some are A+ category students and they require no help from anyone in acing the course. Even if you give these A+ students the solutions they won't take a look at them. Then, there are some students who are happy to get a B for various reasons ((a) do not have the intellectual firepower, (b) not enough time due to other responsibilities etc.) So, if someone is willing to help out these B category students or if enough of these B category students try to pool their resources and solve the problems, is that wrong? To paraphrase from the website: PE is for education and entertainment.

How are you educating people by denying them access to some material which might help them understand what is it that they need to learn to become better at solving PE problems?