(STRATEGY
    INNERMOST)

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