JavaScript Max Challenge

max_challenge.js

/**
 *	JavaScript Max Challenge:
 *		A function that returns the greater of 2 numbers
 *		without using math.min, math.max, >, <, ==, !=
 *
 *		ie:
 *			given a > b
 *			assert max(a, b) == a
 *
 *	Solution:
 *		if a > b then a - b < 0
 *		if n < 0 then n + Math.abs(n) == 0
 *		JavaScript coerces 0 to false
 *
 *		ie:
 *			(a > b) && ((n = a - b) < 0)
 *			(n < 0) && (n + Math.abs(n) == 0)
 *			(0 == false) == true
 *
 *	Tests:
 *		max(8,  9) // 9
 *		max(8, -9) // 8
 */	
function max (a, b) {
	var n = a - b;
	var d = n + Math.abs(n);
	return d ? a : b;
}