(VAR x y )
(STRATEGY INNERMOST)
(RULES 
        not(true) -> false
        not(false) -> true
        odd(0) -> false
        odd(s(x)) -> not(odd(x))
        +(x,0) -> x
        +(x,s(y)) -> s(+(x,y))
        +(s(x),y) -> s(+(x,y))
        
)