Project Euler

I like Project Euler.  If you’ve never heard of it, it’s a website with a few hundred math/programming puzzles to solve, and it keeps track of which ones you’ve solved, who else has solved them, etc etc.

Yesterday, I was working on solving one of the problems.  The way you know you’ve solved it is by entering the answer into the website, and they tell you if it’s right.

I wrote some code, ran it, and got an answer.  They said it was wrong.  So I double-checked my code, ran it again, and got the same answer.  Wrong.  I re-wrote the code from scratch, and got the same answer.  Wrong.

Finally, I got fed up and googled the answer.  Someone’s blog listed what they claimed was the answer – but it was wrong.

So I copied the algorithm used by that blogger, and ran it.  It produced my original answer.  Not the answer they posted on their blog – the same answer I had all along.

I submitted it again, trying not to scream in frustration.  This time, it was accepted.

I don’t know why the site didn’t accept my answer the first couple times.  I don’t know why that blogger posted the wrong answer but the correct algorithm.  I guess Project Euler just wanted to waste some of my time?

(If anyone’s interested, you can see my Project Euler profile here.)