(STRATEGY
    INNERMOST)

(VAR
    x y)
(DATATYPES
    A = µX.< 0, s(X) >)
(SIGNATURES
    min :: [A x A] -> A
    max :: [A x A] -> A
    minus :: [A x A] -> A
    gcd :: [A x A] -> A
    any :: [A] -> A)
(RULES
    min(x,0()) -> 0()
    min(0(),y) -> 0()
    min(s(x),s(y)) -> s(min(x,y))
    max(x,0()) -> x
    max(0(),y) -> y
    max(s(x),s(y)) -> s(max(x,y))
    minus(x,0()) -> x
    minus(s(x),s(y)) -> s(minus(x
                               ,any(y)))
    gcd(s(x),s(y)) ->
      gcd(minus(max(x,y),min(x,y))
         ,s(min(x,y)))
    any(s(x)) -> s(s(any(x)))
    any(x) -> x)