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[Moczan]

Andy is using #C and you are listed as using ECMAScript, but what dialect are you using?

I've used Action Script 3, mainly because that's what I use daily and have a nice workspace already set up. Also, I solved a lot of similar problems using C and C++ while I was in school, so most of them were really trivial for me.
I will probably set up a Visual Studio C# and solve other problems with it as I always wanted to learn C# and that seems like a perfect opportunity to get familiar with the basic syntax.

[JMickle]

did it! haha i was completely mind-blocked the other night, using modulus is so obvious now, thinking about it.

[Dialock]

Thanks man, I really appreciate this site you recommended.  Math is not my strong suit, but improving my programming skills to make something else do the work is great.

[imaginationac]

The site seems to be having major MySQL issues at the moment

[Dacke]

I'm really glad this is catching on!

Good job JMickle, I knew you could do it

Dialock, that's why I love programming! I have added you to the high score table

imaginationac, apparently the site has had some trouble keeping up with all the traffic on Sundays (when new problems are added). They are working on upgrading their servers, but at least they are back online again now.

Personally I have been working on a small python "library" with practical functions and classes that are not part of Python. I'm just adding random stuff as I go along, but so far I have functionality for:

Code: (euler.py)

multiply(listOfNumbers)

Permutations(listOfElements/string) {next(), hasNext()}
//generating permutations one at a time, rather than all at once

BooleanPermutations(listSize) {next(), hasNext()}
//for listSize=2, it returns: [False, False], [False, True], [True, False], [True, True]

uniqueItems(listOfItems/string)

arePermutationsOfEachother(list1/string1, list2/string2)

reversed(integer)

isPalindrome(integer)

digitSum(integer)

binomialCoefficient(n, k)

PrimeSieve(limit) {isPrime(integer), getPrimeList()}

primeFactorization(integer)

greatestCommonDevisor(integer1, integer2)

leastCommonDenominator(integer1, integer2)

(The actual names in the library are a bit shorter though)

[Ashkin]

... Wait, you're supposed to program functions to solve these problems? No wonder trying to solve the first one in my head was so hard.
Anyway, just registered:
17340617327248_4330b9cda8e862e6254c2c02d799836f
I'll probably be terrible at this, but hey, it's worth a try.

[Dacke]

Hehe, yeah, that's the whole point

Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.

(But the first problem can be solved in your head, if you know the right formula(s). When you complete the problem you'll get access to a secret forum thread, where you can learn how )

But anyway, glad to have you aboard!

[imaginationac]

Here's my key:

50667612327256_708fa68d07e1623bed1580aea227b9a0

[Ashkin]

Is problem 3 supposed to take up a lot of CPU and take forever (stupid default script timeout), or am I just doing something terribly, terribly wrong?

[mokesmoe]

If it's taking forever you are doing something at least slightly wrong.

Are you stopping the script at some point? You make it sound like you aren't.

[Ashkin]

If it's taking forever you are doing something at least slightly wrong.

Are you stopping the script at some point? You make it sound like you aren't.

Here's my code. FIX IT.

Code:

var largestnum:int;
for (var num:int = 1; num < 600851475143 / 2; num++)
{
for (var i:int = 3; i < Math.sqrt(num); i++)
{
if (600851475143 % num != 0) break;
if (i == (Math.sqrt(num) - 1)) trace(num);
if (num % i == 0) break;
}
}
trace(largestnum);

I had a (I think) stupider approach before, but even this times out (I hate FlashDevelop sometimes.)

[Moczan]

FlashDevelop is just an IDE, you can't hate it for timing out cause that's FlashPlayer's work  Also your code doesn't do anything. You should look up integer factorization to solve this problem.

[Ashkin]

I already fixed it. On to problem 4 now.
Man, I feel stupid.

[mokesmoe]

I misunderstood timing out. I though you meant you letting it run until it timed out, not that it timed out before finishing.

Anyways, I used a different method of solving it than checking each value:

I just kept dividing it by numbers, staring with two and going up by one whenever when it isn't divisible. The final number I use when the starting number reaches one is the largest prime factor.

Basically I take out prime factors one at a time until I've reached the last one.


Also nothing seems to ever change largestnum in your code and your if statement for trace(num) seems like it would never fire. (Unless sqrt returns an int.)

EDIT: ninja'd but oh well.

[Toeofdoom]

I haven't done any for a while, but this is mine:


and a friend key: 10848697140136_72f6d8fa7b0732794b402f3dbeb406e6
I might have to try some more soon.

I managed to get in the first 30 for problem #345, but it was the easiest of 5 that came out at the same time. It's interesting seeing all the tricks you build up over time.