Big-O notation allows us to quickly estimate an upper bound on the time/space efficiency
of methods. Because Big-O estimates allow function arguments to be arbitrarily
large integers, we treat methods as algorithms by ignoring the space requirements
imposed by Java and a particular computing environment. In addition to
Big-O notation, we also looked at Big- notation (for lower bounds) and Big-
notation (when the upper bound and lower bound are roughly the same).
Run-time analysis allows methods to be tested on a specific computer. But the
estimates produced are often very crude, especially in a multiprogramming environment.
Run-time tools include the currentTimeMillis( ) method and several methods
from the Random class.
