OJ Board

No such problem here, but I haven't submitted code in several years. :-) In any case, you'd have to consider arbitrary parenthesis setting, so (hint:) infix notation might not be the best possible data representation.

/* Steinar */

You are sort of on the right track; but remember, you can also have (1-2)x(3+(4-5)) etc...

And yes, I solved it, but it's ages ago (as you can see, my last submitted run on it is from 2002). I still have the source, but I doubt this forum exists for trading solutions :-)

/* Steinar */

No, I didn't use recursion, but you can solve the problem recursively if you'd like (I know that at least one of the solutions are written recursively).

/* Steinar */

It was my fault after all -- I rewrote the parser once again and fixed a minor bug, and now it got accepted :-)

I tried to submit 549 with a lot of different algorithms and parser twists, but I always ended up getting WA... Finally, I added some basic sanity checks to the input parser... They failed. I've tried making a _very_ flexible parser, but still no luck... My algorithm is more than fast enough (~0.2se...