(VAR u x y z )
(STRATEGY INNERMOST)
(RULES 
        f(a(x), y, s(z), u) -> f(a(b), y, z, g(x, y, s(z), u))
        g(x, y, z, u) -> h(x, y, z, u)
        h(b, y, z, u) -> f(y, y, z, u)
        a(b) -> c
        
)