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Project Euler

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Re: Project Euler

#141

Post by johnsonjo »

jackweirdy wrote: post #21
delibes wrote: post #9

Ah, memories. Back in 2010 I whinged to colleagues who were using their fancy functional languages to solve problem 1 inefficiently in 2 lines of code... " Project Euler problem 1 :- It helps to know the sum of (1 .. x) is 0.5 * n * (n+1). Multiples of 3 less than 1000 are (3 .. 999) == (1 .. 333) * 3 = 0.5 * 333 * 334 * 3 = 166833 Multiples of 5 less than 1000 are (5 .. 995) == (1 .. 199) * 5 = 0.5 * 199 * 200 * 5 =…

> It helps to know the sum of (1 .. x) is 0.5 * n * (n+1) This is cool. As someone out of full time education, and who dropped maths relatively early, where’s a good place to start learning some of this stuff? By stuff I mean things related to algebra and whatever the black magic I quoted is

Honestly math is filled with cool stuff like this. In fact sometimes I wish I would have done a math minor or major at University instead of just a Computer Science major and Information Systems minor (I’m finishing my undergrad in the spring.)

Combinatorics is one of my favorite fields I always feel it has a lot of cool gems like that one and the proofs are often really intuitive. Combinatorics is all about counting things like the number of possible poker hands given a single deck or the number of ways you can seat 4 people around a table.

It was already mentioned below but, discrete math is another good one. Discrete math includes combinatorics, graph theory, set theory, logic, and number theory. All of these have really cool little tidbits of information. My Discrete Math course was my favorite class at university so far. One of the first random bits of information I learned in that class was that any number is divisible by 9 if the sum of it’s digits are divisible by 9 this was posed to us in one of our first homeworks to be proven or disproven and we were able to prove it using some algebra.

Re: Project Euler

#142

Post by johnsonjo »

epicide wrote: post #137
abhiyerra wrote: post #94

Earlier quoted context omitted.

I am the same though I'm only 30. I no longer seek out puzzles but to solve interesting real world problems. The time you put into a challenging Euler puzzle, you can use React/Rails/NodeJs/Go/Rust/lang du jour to solve real world problem, helping real people. Also as a liberal arts in programming, Euler, is fun in the sense of a well done proof is fun in math. If that is your thing you'll enjoy Euler, otherwise as i…

I definitely agree that puzzles/challenges for their own sake are pretty pointlesss. However, I also think (guided) puzzles/challenges are really good for learning new tools/languages. It can be hard to just sit down in front of a real world type problem with even just one new tool and know what to do with it. The best approach is probably somewhere in the middle. Best example I've seen of this are the "workshopper"…

I second that. The NodeSchool [1] workshops are awesome.

[1] http://nodeschool.io

Re: Project Euler

#143

Post by alanbernstein »

ronnypostsstuff wrote: post #126

Did any of you interview and having a good Project Euler account was positively recognized? This never happened to me. No one seems to know the site. They seem to be mostly interested in Top Coder and similar platforms.

I had an interview screening question once that was very similar to Project Euler type questions. I solved it correctly, and quickly, and that probably helped get me in the door.

Re: Project Euler

#144

Post by fogetti »

minusSeven wrote: post #115

Why is project Euler being shown in hackernews now ? This isn't something new and has been there for long time. I often use the easier problems in project Euler for interviews to test candidates. Having said that the problems in project Euler are more math based in nature.

Can I ask how do you evaluate the candidates with these problems? I mean: do they have to solve similar problems on their daily job as well? Or what is the take-away in your specific case?

Re: Project Euler

#145

Post by StreakyCobra »

BuildTheRobots wrote: post #108

For anyone looking for some less math-based coding challenges than Project Euler, then I highly recommend looking at AdventOfCode. It's presented as an advent calendar (so a challenge per day of December) and when you unlock the first half it gives you a second challenge based in the same domain. There's at least a couple of previous years too, if you just want to crack on and work though something. [1] http://advent…

I discovered AOC this year, I clearly recommend it over ProjectEuler if you want programming challenges that requires less math knowledge to go through.

It is also a great platform to learn a new programming language. I'm using it as an opportunity to improve my (small) knowledge of rust.

[1] https://github.com/StreakyCobra/advent-of-code-2017

Re: Project Euler

#146

Post by macintux »

zaarn wrote: post #103
Nydhal wrote: post #70

Earlier quoted context omitted.

Euler was a mathematician after all. Now thinking about it I wonder what project Djikstra would look like, or say maybe project Stallman.

I think a Project Turing might be an interesting one, solving problems specific to computer science (maybe something like pathfinding, evolutionary algorithms, data structures, etc)

Or simply writing programs against the classic Turing machine. I wrote one out by hand 25 years ago, 3 pages I think to add two integers.

Re: Project Euler

#148

Post by jon_richards »

sevensor wrote: post #38

After hearing about it for years, I decided to start working through Project Euler about two weeks ago. It really is much more about math than programming, although it's a lot of fun to take on the problems with a language that has tail call optimization because so many of the problems involve recurrence relations. I like that the problems are constructed in a way that usually punishes you for trying to use brute for…

I didn't do many, but outside of the first couple, I didn't notice any that had attainable answers without computation.

One example was adding one hundred 100 digit numbers and returning the first 10 digits of the sum. The forums were full of "only the first 11 digits matter", "no the first 12 digits matter because there are 100 different numbers and 10^2 is 100", etc.

No one considered:

000...00x90

111...11x9

000...01x1

Re: Project Euler

#150

Post by otakucode »

indigochill wrote: post #120
Nydhal wrote: post #70

Earlier quoted context omitted.

Euler was a mathematician after all. Now thinking about it I wonder what project Djikstra would look like, or say maybe project Stallman.

There's a Project Rosalind (named after Rosalind Franklin) which is sort of like Project Euler for bioinformatics: http://rosalind.info/about/

Project Rosalind (which has mostly been subsumed by the larger Stepik effort I believe?) is fantastic and a much more directed, progressive setup than Project Euler. I enjoyed PR greatly, and each problem led naturally to the next, whereas PE is just random problems and one might be monstrously difficult and on an utterly different topic than the next. A comprehensive mathematics project that grew in complexity the way PR does for bioinformatics would be unbelievably awesome.
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