#define max( x, y ) ((x) >= (y) ? (x) : (y))
#define min( x, y ) ((x) <= (y) ? (x) : (y))


#define swap( T, x, y ) {              \
	T temporary = (x);             \
                                       \
	(x) = (y);                     \
	(y) = temporary;               \
}