YES (THEORY (AC p m ) ) (VAR x2 x3 x1 x y z ) (RULES m(p(x2,x3),x1) -> p(m(x1,x2) ,m(x1,x3)) m(x2,s(x1)) -> p(m(x1,x2),x2) p(x2,s(x1)) -> s(p(x1,x2)) m(zero(),x1) -> zero() p(zero(),x1) -> x1 p(x,zero()) -> x m(x,zero()) -> zero() p(s(x),y) -> s(p(x,y)) m(s(x),y) -> p(m(x,y),y) m(x,p(y,z)) -> p(m(x,y),m(x,z)) )