The Project Euler thread

[Reincarnate]

Re: The Project Euler thread

Sort by difficulty instead

[rushyrulz]

Re: The Project Euler thread

I tried 206 earlier and failed.

Find the unique positive integer whose square has the form 1_2_3_4_5_6_7_8_9_0,
where each “_” is a single digit.

I lack the mathematical background to make inferences about what these blanks might be. Brute force isn't really an option. There are literally a billion different numbers with that fit that number format and I don't even know where to start on it.

[Reincarnate]

Re: The Project Euler thread

Find x where x^2 = 1_2_3_4_5_6_7_8_9_0

You know the last blank must be a 0.

So now if we divide by 100:

x^2/100 = 1_2_3_4_5_6_7_8_9

(x/10)^2 = 1_2_3_4_5_6_7_8_9

Since the righthand number ends in 9, we know x/10 must end in either 3 or 7.

That should cut things down some.

[danceflashrevo]

Re: The Project Euler thread

Oh hey, I never noticed this thread. I primarily got into programming this/last year and project euler has been fun for me testing out my math skills and my programming skills.

I've solved 1-12, 14, 16, and 20. I'll probably work on 13 now.

[Reincarnate]

Re: The Project Euler thread

Try sorting by difficulty, too -- there are easy / good problems later on in the problem set, too.

[XCV]

Re: The Project Euler thread

bump because site just got unhacked, and also the solution to 175 just blew my god damn mind

too lazy to do 1-100 again



anyone else still bother with this?

[blanky!]

Re: The Project Euler thread

bump again because this thread needs a serious revival

I'll solve some problems when I get home.


85/535

[kommisar]

Re: The Project Euler thread

so I just learned how to code anything a few weeks ago. I'm not inherently great at mathematics but given my field of study I kinda have to get on it quickly.




got a long way to go. Using Java

[infinigon]

Re: The Project Euler thread

Oh sweet, there's a whole sticky thread for PE on FFR?! I'm surprised at the overlap between people interested in these two things...

Anyhow, I've decided to force myself to work through the problems in sequence, so that I can't just skip the harder problems. I'm currently on 156.

How's everyone else doing?

[Soundwave-]

Re: The Project Euler thread

I've considered picking back up PE just so I can claim this thread as my stomping grounds. I don't find most of PE to really be conducive to the kind of practice I find useful, but I've recently been rusting up in programming mostly due to not having time on my hands for more involved things, so it might be worth picking this back up.

[infinigon]

Re: The Project Euler thread

I've considered picking back up PE just so I can claim this thread as my stomping grounds. I don't find most of PE to really be conducive to the kind of practice I find useful, but I've recently been rusting up in programming mostly due to not having time on my hands for more involved things, so it might be worth picking this back up.

Yes, do it!

[infinigon]

Re: The Project Euler thread



Turned out to be pretty straightforward. Moving on! 157 next.

EDIT:



I'll take it. Done 158 ages ago, 159 next...

EDIT:



Well that was quick.

[leonid]

Re: The Project Euler thread

A reminder that this exists

[Soundwave-]

Re: The Project Euler thread

Damn I should get back into this. I've been kinda upset with my algorithmic deficiency lately while not accepting the fact that it means that I should like... you know, practice.

[choof]

Re: The Project Euler thread

legitimately have no fucking clue why i was trying to teach myself basic