reprogram during a competition

[ericand]

If you need a sufficiently small number of values, table lookup will
save space. It just depends on how many you need. In the general
case, an algorithm will save space and table lookup will optimize for speed.

The use of #define will not necessarily save space (except in your
source files, where you don't care). It depends on how you are doing things.
To save space with constants, you want every reference to the value of the
constant to be to the same memory location. If you just use the define, you
will be storing the constant value everywhere it is used.