You have to be kidding. Otherwise, read up on the definition of “commutative” here: http://en.wikipedia.org/wiki/Commutative_property http://en.wikipedia.org/wi

You have to be kidding. Otherwise, read up on the definition of “commutative” here: http://en.wikipedia.org/wiki/Commutative_property http://en.wikipedia.org/wiki/Commutative_property Look for the first occurrence of the word “commutative” in this page: http://en.wikipedia.org/wiki/Floating_point http://en.wikipedia.org/wiki/Floating_point But remember, if both the Wikipedia editors and I are wrong, you only need to produce one pair of operands a and b such that a * b does not produce not the same result(1) as b * a to be vindicated. (1) I suggest we consider all NaN values to be “the same result” for the purpose of this challenge.