1#define noargs() 1 2# define onearg(foo) foo 3 # define twoargs( x , y ) x y 4 # define threeargs( a , b , c ) a b c 5noargs ( ) 6onearg ( 2 ) 7twoargs ( 3 , 4 ) 8threeargs ( 5 , 6 , 7 ) 9