(STRATEGY
    INNERMOST)

(VAR
    x y z)
(DATATYPES
    A = µX.< 0, s(X) >)
(SIGNATURES
    minus :: [A x A] -> A
    quot :: [A x A] -> A
    plus :: [A x A] -> A)
(RULES
    minus(x,0()) -> x
    minus(s(x),s(y)) -> minus(x,y)
    quot(0(),s(y)) -> 0()
    quot(s(x),s(y)) ->
      s(quot(minus(x,y),s(y)))
    plus(0(),y) -> y
    plus(s(x),y) -> s(plus(x,y))
    plus(minus(x,s(0()))
        ,minus(y,s(s(z)))) ->
      plus(minus(y,s(s(z)))
          ,minus(x,s(0())))
    plus(plus(x,s(0()))
        ,plus(y,s(s(z)))) -> plus(plus(y
                                      ,s(s(z)))
                                 ,plus(x,s(0()))))