Coding contest byte: Meet in the middle

scratch-meet-in-the-middle

h1. Meet in the middle
 

Meet in the middle (sometimes called split and merge) is a clever approach which tries to trade off space for time. Much like divide et impera it divides the problem in two and then tries to merge the results. The benefit is that by using quite a bit of memory you can tackle problems of twice the size you could before.
Here are a few applications.