> > Because this: > > if ( a < b ) > > is not the same as this: > > if ( (a-b) < 0 ) > > In what mathematics? In the realm of a finitely-sized set of integers, it is possible for the second test to cause an under- (or over-) flow, whereas this should not be the case for the first test. Jon .......... Jonathan Moore http://www.cis.upenn.edu/~jonm University of Pennsylvania jonm@dsl.cis.upenn.edu