ALgorithm Reference book for problem solving?

Did you actually try solving problems in Knuth? It's a pretty good workout to attempt all the problems up to level 20 or so, and to take a stab at a few 30s. I'm speaking of The Art of Computer Programming, Vol. I ("Fundamental Algorithms") in particular. The coding problems should probably be converted to C, these days, since nobody does embler (or "embly" as Knuth and others like to say) any more. But, the answers in the solutions section will all be in MIX. Emulators are available.