(STRATEGY
    INNERMOST)

(VAR
    x y)
(DATATYPES
    A = µX.< 0, 1, s(X) >)
(SIGNATURES
    f :: [A] -> A
    g :: [A x A] -> A
    + :: [A x A] -> A)
(RULES
    f(0()) -> 1()
    f(s(x)) -> g(x,s(x))
    g(0(),y) -> y
    g(s(x),y) -> g(x,+(y,s(x)))
    +(x,0()) -> x
    +(x,s(y)) -> s(+(x,y))
    g(s(x),y) -> g(x,s(+(y,x))))