Fastest algorithm Discussion

Anyway just for fun and learning I have been messing with algorithms in my head.  Here is the problem:  There is a set of numbers N, Is there a subset of exactly two of them which equal a number Z. 

So for instance, 1,4,6,125,185 and the sum 129.  Would return true. 

What is the fastest exact way to do this for arbitrarily large numbers?

I know one method is to take the largest and smallest (1,129) and move each one up or down depending on < or >.  This method takes O(N) time.

What are the faster algs for this?

>>22 is incognizant to the fact that >>18 made an EBCDIC joke.

Actually Haskell uses Unicode which is compatible with ASCII, but jokes don't always have to be technically correct

>>22 come back to us when you have at least 10 years of experience with differend flavours of IBM mainframes.

>>25
That's such a  long time, I doubt 4chan will be alive then. But I can write you an email.

>>24
UTF-8 you mean?

Language of choice is   cat and echo.