Thread: Project Euler Progress

I just finished question 59, and wondered how many out there are doing project euler questions.

I have completed 1 to 33, 59, and 67.

The reason I have done 59 and 67 out of order is because: I love encryption problems (59), and I used the exact same code from problem 18 for 67, just changed a text file that was being read.

I didn't even know about it, but it looks pretty cool. What sort of mathematics are needed?

So that there is no confusion, this is the site that I meant https://projecteuler.net/

What sort of mathematics are needed?

Not a lot.

It's more about learning algorithms. I find it useful because I did not come from a computer science background with my formal education, so I missed out on algorithms like calculating prime numbers and fastest ways of doing it.

Question 1 is

[Don't answer it here, as it will ruin it for other people]
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.

Find the sum of all the multiples of 3 or 5 below 1000.

As the questions go on, they get harder - You can see how many people have solved each question, and the harder they are, the less people have solved it.

My usual thing is to read the question and then go to wiki to learn more about what the program is asking. I then look around for fast algorithms, because there is no pride in making a program which takes 5 hours to solve. A good example of that is question 10 https://projecteuler.net/problem=10 - If you don't use a very fast way of calculating primes, your program will take a VERY long time to solve.

I would recommend them to anyone - Even the Titans on here like Laserlight, Grumpy, or Salem!

Last I logged in to that site was 4 years ago. My progress at that time was 55/485 problems. I am surprised by the sheer number of problems they have added over the years because it used to be around 200+ at that time. Thanks for reminding, time to start cracking some problems I guess.

Originally Posted by Click_here

It's more about learning algorithms. I find it useful because I did not come from a computer science background with my formal education, so I missed out on algorithms like calculating prime numbers and fastest ways of doing it.

I don't agree. Project Euler is definitely about mathematics and very little about algorithmics.

Sure you can find a naive solution to some of the problems with only a basic mathematical background with the help of some algorithm designed by you. But right from the start, the more efficient solutions (which can be found on the solution PDFs or the forum posts, once we solve the problem) reveal one needs a deeper grasp of mathematics in order to solve the problems. Starting with Problem 1, you are already dealing with factorization. Problem 2 can be better solved with sets or alternatively, as described in the solution pdf, with an off-computing algebraic proof of a recursive relation. Meanwhile other problems can be solved, even through naive methods, only if one dominates certain mathematical fields.

There is a wealth of knowledge to be gained from Project Euler no doubt. Particularly in the area of algorithms, since right from the start it invites the user to think about -- and eventually get a feel for -- efficiency. But many problems require a deep understanding of mathematics in various fields (often different from mathematical field represented on the problem description) in order to be solved in a way that makes computational sense.